642224008 has 8 divisors (see below), whose sum is σ = 1204170030. Its totient is φ = 321112000.

The previous prime is 642223991. The next prime is 642224017. The reversal of 642224008 is 800422246.

It can be written as a sum of positive squares in only one way, i.e., 642014244 + 209764 = 25338^2 + 458^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40138993 + ... + 40139008.

Almost surely, 2^642224008 is an apocalyptic number.

It is an amenable number.

642224008 is a deficient number, since it is larger than the sum of its proper divisors (561946022).

642224008 is a wasteful number, since it uses less digits than its factorization.

642224008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80278007 (or 80278003 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 28.

The square root of 642224008 is about 25342.1389783893. The cubic root of 642224008 is about 862.7709469555.

The spelling of 642224008 in words is "six hundred forty-two million, two hundred twenty-four thousand, eight".