639456345 has 24 divisors (see below), whose sum is σ = 1209154752. Its totient is φ = 310039200.

The previous prime is 639456341. The next prime is 639456347. The reversal of 639456345 is 543654936.

639456345 is a `hidden beast` number, since 6 + 3 + 9 + 4 + 5 + 634 + 5 = 666.

It is not a de Polignac number, because 639456345 - 2² = 639456341 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 639456345.

It is not an unprimeable number, because it can be changed into a prime (639456341) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 645421 + ... + 646410.

It is an arithmetic number, because the mean of its divisors is an integer number (50381448).

Almost surely, 2^639456345 is an apocalyptic number.

It is an amenable number.

639456345 is a deficient number, since it is larger than the sum of its proper divisors (569698407).

639456345 is a wasteful number, since it uses less digits than its factorization.

639456345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1291853 (or 1291850 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 45.

The square root of 639456345 is about 25287.4740731454. The cubic root of 639456345 is about 861.5297924717.

The spelling of 639456345 in words is "six hundred thirty-nine million, four hundred fifty-six thousand, three hundred forty-five".