639599490 has 80 divisors (see below), whose sum is σ = 1726021440. Its totient is φ = 169944480.

The previous prime is 639599459. The next prime is 639599503. The reversal of 639599490 is 94995936.

639599490 is a `hidden beast` number, since 6 + 3 + 9 + 599 + 49 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 250641 + ... + 253179.

It is an arithmetic number, because the mean of its divisors is an integer number (21575268).

Almost surely, 2^639599490 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639599490, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (863010720).

639599490 is an abundant number, since it is smaller than the sum of its proper divisors (1086421950).

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

639599490 is a wasteful number, since it uses less digits than its factorization.

639599490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2869 (or 2860 counting only the distinct ones).

The product of its (nonzero) digits is 2361960, while the sum is 54.

The square root of 639599490 is about 25290.3042686323. The cubic root of 639599490 is about 861.5940733680.

The spelling of 639599490 in words is "six hundred thirty-nine million, five hundred ninety-nine thousand, four hundred ninety".