1,722,721

7 × 11 × 13 × 1721

Starting at 1,722,721, the Collatz iteration reaches 1 after 132 steps. The first transition is 5168164; the starting value is odd with 16 positive divisors.

Prime Factor Structure

Factorization String 7 × 11 × 13 × 1721

Distinct Prime Factors 4

Square Status No

Abundance Measure Deficient

Analytical Properties

Total Divisors 16

Divisor Sum (σ) 2,314,368

Proper Divisor Sum 591,647

Digit Sum / Digital Root 22 (Root: 4)

Adjacent Primes #1722719 ← → #1722731

Radix Representation

Decimal	1722721
Binary	110100100100101100001 (21 bits)
Octal	0o6444541
Hexadecimal	0x1A4961

Divisor Catalog (16)

1 7 11 13 77 91 143 1,001 1,721 12,047 18,931 22,373 132,517 156,611 246,103 1,722,721

Collatz Trajectory (132 steps to reach 1)

Iterative sequence n → n/2 (if even) or 3n+1 (if odd):

1,722,721 5,168,164 2,584,082 1,292,041 3,876,124 1,938,062 969,031 2,907,094 1,453,547 4,360,642 2,180,321 6,540,964 3,270,482 1,635,241 4,905,724 2,452,862 1,226,431 3,679,294 1,839,647 5,518,942 2,759,471 8,278,414 4,139,207 12,417,622 6,208,811 18,626,434 9,313,217 27,939,652 13,969,826 6,984,913 20,954,740 10,477,370 5,238,685 15,716,056 7,858,028 3,929,014 1,964,507 5,893,522 2,946,761 8,840,284 4,420,142 2,210,071 6,630,214 3,315,107 9,945,322 4,972,661 14,917,984 7,458,992 3,729,496 1,864,748 932,374 466,187 1,398,562 699,281 2,097,844 1,048,922 524,461 1,573,384 786,692 393,346

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