642320525 has 24 divisors (see below), whose sum is σ = 993013824. Its totient is φ = 400406400.

The previous prime is 642320521. The next prime is 642320531. The reversal of 642320525 is 525023246.

It is not a de Polignac number, because 642320525 - 2² = 642320521 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642320521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 164912 + ... + 168761.

It is an arithmetic number, because the mean of its divisors is an integer number (41375576).

Almost surely, 2^642320525 is an apocalyptic number.

It is an amenable number.

642320525 is a deficient number, since it is larger than the sum of its proper divisors (350693299).

642320525 is a wasteful number, since it uses less digits than its factorization.

642320525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333701 (or 333696 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 29.

The square root of 642320525 is about 25344.0431857271. The cubic root of 642320525 is about 862.8141654646.

The spelling of 642320525 in words is "six hundred forty-two million, three hundred twenty thousand, five hundred twenty-five".