639349790 has 8 divisors (see below), whose sum is σ = 1150829640. Its totient is φ = 255739912.

The previous prime is 639349693. The next prime is 639349793. The reversal of 639349790 is 97943936.

It is a happy number.

639349790 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639349793) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31967480 + ... + 31967499.

It is an arithmetic number, because the mean of its divisors is an integer number (143853705).

Almost surely, 2^639349790 is an apocalyptic number.

639349790 is a deficient number, since it is larger than the sum of its proper divisors (511479850).

639349790 is a wasteful number, since it uses less digits than its factorization.

639349790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63934986.

The product of its (nonzero) digits is 1102248, while the sum is 50.

The square root of 639349790 is about 25285.3671122252. The cubic root of 639349790 is about 861.4819365040.

The spelling of 639349790 in words is "six hundred thirty-nine million, three hundred forty-nine thousand, seven hundred ninety".