642624836 has 12 divisors (see below), whose sum is σ = 1285249728. Its totient is φ = 275410632.

The previous prime is 642624817. The next prime is 642624839. The reversal of 642624836 is 638426246.

642624836 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 642624793 and 642624802.

It is not an unprimeable number, because it can be changed into a prime (642624839) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11475416 + ... + 11475471.

It is an arithmetic number, because the mean of its divisors is an integer number (107104144).

Almost surely, 2^642624836 is an apocalyptic number.

It is an amenable number.

642624836 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

642624836 is a wasteful number, since it uses less digits than its factorization.

642624836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22950898 (or 22950896 counting only the distinct ones).

The product of its digits is 331776, while the sum is 41.

The square root of 642624836 is about 25350.0460749088. The cubic root of 642624836 is about 862.9504019059.

The spelling of 642624836 in words is "six hundred forty-two million, six hundred twenty-four thousand, eight hundred thirty-six".