129597531 has 16 divisors (see below), whose sum is σ = 199041024. Its totient is φ = 73471104.

The previous prime is 129597527. The next prime is 129597541. The reversal of 129597531 is 135795921.

It is not a de Polignac number, because 129597531 - 2² = 129597527 is a prime.

It is a super-2 number, since 2×129597531² = 33591040082591922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (129597521) 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, 21630 + ... + 26963.

It is an arithmetic number, because the mean of its divisors is an integer number (12440064).

Almost surely, 2^129597531 is an apocalyptic number.

129597531 is a deficient number, since it is larger than the sum of its proper divisors (69443493).

129597531 is a wasteful number, since it uses less digits than its factorization.

129597531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48730.

The product of its digits is 85050, while the sum is 42.

The square root of 129597531 is about 11384.0911363183. The cubic root of 129597531 is about 506.0563855260.

The spelling of 129597531 in words is "one hundred twenty-nine million, five hundred ninety-seven thousand, five hundred thirty-one".