129115431 has 32 divisors (see below), whose sum is σ = 202272000. Its totient is φ = 81173664.

The previous prime is 129115373. The next prime is 129115433. The reversal of 129115431 is 134511921.

It is a happy number.

It is not a de Polignac number, because 129115431 - 2⁹ = 129114919 is a prime.

It is a super-2 number, since 2×129115431² = 33341589044631522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 129115395 and 129115404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129115433) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 149880 + ... + 150738.

It is an arithmetic number, because the mean of its divisors is an integer number (6321000).

Almost surely, 2^129115431 is an apocalyptic number.

129115431 is a deficient number, since it is larger than the sum of its proper divisors (73156569).

129115431 is a wasteful number, since it uses less digits than its factorization.

129115431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1180 (or 1174 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 129115431 is about 11362.8971217731. The cubic root of 129115431 is about 505.4280995571.

The spelling of 129115431 in words is "one hundred twenty-nine million, one hundred fifteen thousand, four hundred thirty-one".