639787936 has 12 divisors (see below), whose sum is σ = 1259582562. Its totient is φ = 319893952.

The previous prime is 639787933. The next prime is 639787961.

639787936 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in only one way, i.e., 521848336 + 117939600 = 22844^2 + 10860^2 .

It is a super-2 number, since 2×639787936² = 818657206102280192, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (639787933) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9996655 + ... + 9996718.

Almost surely, 2^639787936 is an apocalyptic number.

It is an amenable number.

639787936 is a deficient number, since it is larger than the sum of its proper divisors (619794626).

639787936 is a wasteful number, since it uses less digits than its factorization.

639787936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19993383 (or 19993375 counting only the distinct ones).

The product of its digits is 10287648, while the sum is 58.

The square root of 639787936 is about 25294.0296512833. The cubic root of 639787936 is about 861.6786825733.

The spelling of 639787936 in words is "six hundred thirty-nine million, seven hundred eighty-seven thousand, nine hundred thirty-six".