129061631 has 4 divisors (see below), whose sum is σ = 130987992. Its totient is φ = 127135272.

The previous prime is 129061613. The next prime is 129061679. The reversal of 129061631 is 136160921.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 129061631 - 2⁶ = 129061567 is a prime.

It is a super-2 number, since 2×129061631² = 33313809192760322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 129061594 and 129061603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129961631) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 963080 + ... + 963213.

It is an arithmetic number, because the mean of its divisors is an integer number (32746998).

Almost surely, 2^129061631 is an apocalyptic number.

129061631 is a deficient number, since it is larger than the sum of its proper divisors (1926361).

129061631 is an equidigital number, since it uses as much as digits as its factorization.

129061631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1926360.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 129061631 is about 11360.5295211095. The cubic root of 129061631 is about 505.3578889731.

The spelling of 129061631 in words is "one hundred twenty-nine million, sixty-one thousand, six hundred thirty-one".