642918925 has 24 divisors (see below), whose sum is σ = 875292192. Its totient is φ = 464568000.

The previous prime is 642918917. The next prime is 642918949. The reversal of 642918925 is 529819246.

It is not a de Polignac number, because 642918925 - 2³ = 642918917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35730 + ... + 50620.

It is an arithmetic number, because the mean of its divisors is an integer number (36470508).

Almost surely, 2^642918925 is an apocalyptic number.

It is an amenable number.

642918925 is a deficient number, since it is larger than the sum of its proper divisors (232373267).

642918925 is a wasteful number, since it uses less digits than its factorization.

642918925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15069 (or 15064 counting only the distinct ones).

The product of its digits is 311040, while the sum is 46.

The square root of 642918925 is about 25355.8459728718. The cubic root of 642918925 is about 863.0820212182.

The spelling of 642918925 in words is "six hundred forty-two million, nine hundred eighteen thousand, nine hundred twenty-five".