129501631 has 16 divisors (see below), whose sum is σ = 159672384. Its totient is φ = 102495744.

The previous prime is 129501623. The next prime is 129501679. The reversal of 129501631 is 136105921.

It is a cyclic number.

It is not a de Polignac number, because 129501631 - 2³ = 129501623 is a prime.

It is a super-2 number, since 2×129501631² = 33541344863320322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 129501631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129501731) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3960 + ... + 16573.

It is an arithmetic number, because the mean of its divisors is an integer number (9979524).

Almost surely, 2^129501631 is an apocalyptic number.

129501631 is a deficient number, since it is larger than the sum of its proper divisors (30170753).

129501631 is a wasteful number, since it uses less digits than its factorization.

129501631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20610.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 129501631 is about 11379.8783385412. The cubic root of 129501631 is about 505.9315303106.

The spelling of 129501631 in words is "one hundred twenty-nine million, five hundred one thousand, six hundred thirty-one".