639647344476 has 120 divisors (see below), whose sum is σ = 1911956382336. Its totient is φ = 182669243040.

The previous prime is 639647344459. The next prime is 639647344529. The reversal of 639647344476 is 674443746936.

639647344476 is a `hidden beast` number, since 6 + 3 + 96 + 4 + 73 + 4 + 4 + 476 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4766935 + ... + 4899281.

Almost surely, 2^639647344476 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639647344476, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (955978191168).

639647344476 is an abundant number, since it is smaller than the sum of its proper divisors (1272309037860).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639647344476 is a wasteful number, since it uses less digits than its factorization.

639647344476 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134501 (or 134490 counting only the distinct ones).

The product of its digits is 219469824, while the sum is 63.

The spelling of 639647344476 in words is "six hundred thirty-nine billion, six hundred forty-seven million, three hundred forty-four thousand, four hundred seventy-six".