125128731 has 32 divisors (see below), whose sum is σ = 208434688. Its totient is φ = 65007360.

The previous prime is 125128727. The next prime is 125128777. The reversal of 125128731 is 137821521.

It is not a de Polignac number, because 125128731 - 2² = 125128727 is a prime.

It is a super-2 number, since 2×125128731² = 31314398643340722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (125128331) 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, 14871 + ... + 21711.

It is an arithmetic number, because the mean of its divisors is an integer number (6513584).

Almost surely, 2^125128731 is an apocalyptic number.

125128731 is a deficient number, since it is larger than the sum of its proper divisors (83305957).

125128731 is a wasteful number, since it uses less digits than its factorization.

125128731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6931.

The product of its digits is 3360, while the sum is 30.

The square root of 125128731 is about 11186.0954313827. The cubic root of 125128731 is about 500.1715824455.

It can be divided in two parts, 1251 and 28731, that multiplied together give a triangular number (35942481 = T₈₄₇₈).

The spelling of 125128731 in words is "one hundred twenty-five million, one hundred twenty-eight thousand, seven hundred thirty-one".