642635122 has 16 divisors (see below), whose sum is σ = 1037391192. Its totient is φ = 297457920.

The previous prime is 642635117. The next prime is 642635141. The reversal of 642635122 is 221536246.

It can be written as a sum of positive squares in 4 ways, for example, as 270569601 + 372065521 = 16449^2 + 19289^2 .

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, 152853 + ... + 157000.

Almost surely, 2^642635122 is an apocalyptic number.

642635122 is a deficient number, since it is larger than the sum of its proper divisors (394756070).

642635122 is a wasteful number, since it uses less digits than its factorization.

642635122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 309933.

The product of its digits is 17280, while the sum is 31.

The square root of 642635122 is about 25350.2489534127. The cubic root of 642635122 is about 862.9550060752.

The spelling of 642635122 in words is "six hundred forty-two million, six hundred thirty-five thousand, one hundred twenty-two".