642797136 has 60 divisors (see below), whose sum is σ = 1800642688. Its totient is φ = 214062912.

The previous prime is 642797117. The next prime is 642797137. The reversal of 642797136 is 631797246.

642797136 is a `hidden beast` number, since 6 + 427 + 97 + 136 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 642797091 and 642797100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642797137) 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 11 ways as a sum of consecutive naturals, for example, 298881 + ... + 301023.

Almost surely, 2^642797136 is an apocalyptic number.

It is an amenable number.

642797136 is an abundant number, since it is smaller than the sum of its proper divisors (1157845552).

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

642797136 is a wasteful number, since it uses less digits than its factorization.

642797136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4240 (or 4231 counting only the distinct ones).

The product of its digits is 381024, while the sum is 45.

The square root of 642797136 is about 25353.4442630582. Note that the first 3 decimals coincide. The cubic root of 642797136 is about 863.0275195124.

The spelling of 642797136 in words is "six hundred forty-two million, seven hundred ninety-seven thousand, one hundred thirty-six".