642508263 has 18 divisors (see below), whose sum is σ = 958983792. Its totient is φ = 414515880.

The previous prime is 642508231. The next prime is 642508331. The reversal of 642508263 is 362805246.

642508263 is a `hidden beast` number, since 642 + 5 + 0 + 8 + 2 + 6 + 3 = 666.

It is not a de Polignac number, because 642508263 - 2⁵ = 642508231 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642508463) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 28495 + ... + 45792.

Almost surely, 2^642508263 is an apocalyptic number.

642508263 is a deficient number, since it is larger than the sum of its proper divisors (316475529).

642508263 is a wasteful number, since it uses less digits than its factorization.

642508263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74355 (or 74321 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 642508263 is about 25347.7467045890. The cubic root of 642508263 is about 862.8982186335.

The spelling of 642508263 in words is "six hundred forty-two million, five hundred eight thousand, two hundred sixty-three".