129661572 has 12 divisors (see below), whose sum is σ = 302543696. Its totient is φ = 43220520.

The previous prime is 129661547. The next prime is 129661591. The reversal of 129661572 is 275166921.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×129661572² = 33624246507022368, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 129661572.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5402554 + ... + 5402577.

Almost surely, 2^129661572 is an apocalyptic number.

129661572 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

129661572 is an abundant number, since it is smaller than the sum of its proper divisors (172882124).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129661572 is a wasteful number, since it uses less digits than its factorization.

129661572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10805138 (or 10805136 counting only the distinct ones).

The product of its digits is 45360, while the sum is 39.

The square root of 129661572 is about 11386.9035299330. The cubic root of 129661572 is about 506.1397282151.

The spelling of 129661572 in words is "one hundred twenty-nine million, six hundred sixty-one thousand, five hundred seventy-two".