642634623 has 12 divisors (see below), whose sum is σ = 933617880. Its totient is φ = 425945616.

The previous prime is 642634607. The next prime is 642634627. The reversal of 642634623 is 326436246.

642634623 is a `hidden beast` number, since 6 + 4 + 26 + 3 + 4 + 623 = 666.

It is not a de Polignac number, because 642634623 - 2⁴ = 642634607 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642634627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 204813 + ... + 207926.

It is an arithmetic number, because the mean of its divisors is an integer number (77801490).

Almost surely, 2^642634623 is an apocalyptic number.

642634623 is a deficient number, since it is larger than the sum of its proper divisors (290983257).

642634623 is a wasteful number, since it uses less digits than its factorization.

642634623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412918 (or 412915 counting only the distinct ones).

The product of its digits is 124416, while the sum is 36.

The square root of 642634623 is about 25350.2391112983. The cubic root of 642634623 is about 862.9547827163.

It can be divided in two parts, 64263 and 4623, that added together give a palindrome (68886).

The spelling of 642634623 in words is "six hundred forty-two million, six hundred thirty-four thousand, six hundred twenty-three".