129925918 has 4 divisors (see below), whose sum is σ = 194888880. Its totient is φ = 64962958.

The previous prime is 129925891. The next prime is 129925967. The reversal of 129925918 is 819529921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 819529921 = 7 ⋅117075703.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32481478 + ... + 32481481.

It is an arithmetic number, because the mean of its divisors is an integer number (48722220).

Almost surely, 2^129925918 is an apocalyptic number.

129925918 is a deficient number, since it is larger than the sum of its proper divisors (64962962).

129925918 is an equidigital number, since it uses as much as digits as its factorization.

129925918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64962961.

The product of its digits is 116640, while the sum is 46.

The square root of 129925918 is about 11398.5050774213. The cubic root of 129925918 is about 506.4834568629.

The spelling of 129925918 in words is "one hundred twenty-nine million, nine hundred twenty-five thousand, nine hundred eighteen".