642136708 has 6 divisors (see below), whose sum is σ = 1123739246. Its totient is φ = 321068352.

The previous prime is 642136687. The next prime is 642136757. The reversal of 642136708 is 807631246.

It can be written as a sum of positive squares in only one way, i.e., 638168644 + 3968064 = 25262^2 + 1992^2 .

It is a super-2 number, since 2×642136708² = 824679103522154528, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80267085 + ... + 80267092.

Almost surely, 2^642136708 is an apocalyptic number.

It is an amenable number.

642136708 is a deficient number, since it is larger than the sum of its proper divisors (481602538).

642136708 is a wasteful number, since it uses less digits than its factorization.

642136708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160534181 (or 160534179 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 642136708 is about 25340.4164922363. The cubic root of 642136708 is about 862.7318519171.

The spelling of 642136708 in words is "six hundred forty-two million, one hundred thirty-six thousand, seven hundred eight".