639880450 has 48 divisors (see below), whose sum is σ = 1311344640. Its totient is φ = 230360000.

The previous prime is 639880441. The next prime is 639880477. The reversal of 639880450 is 54088936.

It is a junction number, because it is equal to n+sod(n) for n = 639880397 and 639880406.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 49791 + ... + 61309.

It is an arithmetic number, because the mean of its divisors is an integer number (27319680).

Almost surely, 2^639880450 is an apocalyptic number.

639880450 is an abundant number, since it is smaller than the sum of its proper divisors (671464190).

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

639880450 is a wasteful number, since it uses less digits than its factorization.

639880450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11643 (or 11638 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 43.

The square root of 639880450 is about 25295.8583566559. The cubic root of 639880450 is about 861.7202137823.

The spelling of 639880450 in words is "six hundred thirty-nine million, eight hundred eighty thousand, four hundred fifty".