642506136 has 32 divisors (see below), whose sum is σ = 1661655600. Its totient is φ = 206783360.

The previous prime is 642506113. The next prime is 642506149. The reversal of 642506136 is 631605246.

It is a junction number, because it is equal to n+sod(n) for n = 642506097 and 642506106.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 460875 + ... + 462266.

Almost surely, 2^642506136 is an apocalyptic number.

It is an amenable number.

642506136 is an abundant number, since it is smaller than the sum of its proper divisors (1019149464).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642506136 is a wasteful number, since it uses less digits than its factorization.

642506136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 923179 (or 923175 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 33.

The square root of 642506136 is about 25347.7047481621. The cubic root of 642506136 is about 862.8972664349.

The spelling of 642506136 in words is "six hundred forty-two million, five hundred six thousand, one hundred thirty-six".