642631125 has 16 divisors (see below), whose sum is σ = 1069338816. Its totient is φ = 342736400.

The previous prime is 642631123. The next prime is 642631159. The reversal of 642631125 is 521136246.

It is not a de Polignac number, because 642631125 - 2¹ = 642631123 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 642631092 and 642631101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642631123) 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, 856467 + ... + 857216.

It is an arithmetic number, because the mean of its divisors is an integer number (66833676).

Almost surely, 2^642631125 is an apocalyptic number.

It is an amenable number.

642631125 is a deficient number, since it is larger than the sum of its proper divisors (426707691).

642631125 is a wasteful number, since it uses less digits than its factorization.

642631125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1713701 (or 1713691 counting only the distinct ones).

The product of its digits is 8640, while the sum is 30.

The square root of 642631125 is about 25350.1701177724. The cubic root of 642631125 is about 862.9532169633.

The spelling of 642631125 in words is "six hundred forty-two million, six hundred thirty-one thousand, one hundred twenty-five".