639244413 has 8 divisors (see below), whose sum is σ = 947028800. Its totient is φ = 426162924.

The previous prime is 639244399. The next prime is 639244469. The reversal of 639244413 is 314442936.

It is a happy number.

639244413 is a `hidden beast` number, since 639 + 2 + 4 + 4 + 4 + 13 = 666.

It is not a de Polignac number, because 639244413 - 2⁶ = 639244349 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639244813) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11837833 + ... + 11837886.

It is an arithmetic number, because the mean of its divisors is an integer number (118378600).

Almost surely, 2^639244413 is an apocalyptic number.

It is an amenable number.

639244413 is a deficient number, since it is larger than the sum of its proper divisors (307784387).

639244413 is a wasteful number, since it uses less digits than its factorization.

639244413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23675728 (or 23675722 counting only the distinct ones).

The product of its digits is 62208, while the sum is 36.

The square root of 639244413 is about 25283.2832717588. The cubic root of 639244413 is about 861.4346043699.

It can be divided in two parts, 6392 and 44413, that added together give a palindrome (50805).

The spelling of 639244413 in words is "six hundred thirty-nine million, two hundred forty-four thousand, four hundred thirteen".