642925 has 6 divisors (see below), whose sum is σ = 797258. Its totient is φ = 514320.

The previous prime is 642907. The next prime is 642931. The reversal of 642925 is 529246.

It can be written as a sum of positive squares in 3 ways, for example, as 56169 + 586756 = 237^2 + 766^2 .

It is not a de Polignac number, because 642925 - 2⁷ = 642797 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 642893 and 642902.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12834 + ... + 12883.

2⁶⁴²⁹²⁵ is an apocalyptic number.

It is an amenable number.

642925 is a deficient number, since it is larger than the sum of its proper divisors (154333).

642925 is a wasteful number, since it uses less digits than its factorization.

642925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25727 (or 25722 counting only the distinct ones).

The product of its digits is 4320, while the sum is 28.

The square root of 642925 is about 801.8260409840. The cubic root of 642925 is about 86.3084739657.

The spelling of 642925 in words is "six hundred forty-two thousand, nine hundred twenty-five".