639485649 has 24 divisors (see below), whose sum is σ = 1014117312. Its totient is φ = 385089120.

The previous prime is 639485579. The next prime is 639485657. The reversal of 639485649 is 946584936.

639485649 is a `hidden beast` number, since 6 + 39 + 48 + 564 + 9 = 666.

639485649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 639485649 - 2⁹ = 639485137 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 639485595 and 639485604.

It is not an unprimeable number, because it can be changed into a prime (639485659) 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, 5029 + ... + 36114.

It is an arithmetic number, because the mean of its divisors is an integer number (42254888).

Almost surely, 2^639485649 is an apocalyptic number.

It is an amenable number.

639485649 is a deficient number, since it is larger than the sum of its proper divisors (374631663).

639485649 is a wasteful number, since it uses less digits than its factorization.

639485649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41317 (or 41314 counting only the distinct ones).

The product of its digits is 5598720, while the sum is 54.

The square root of 639485649 is about 25288.0534838093. The cubic root of 639485649 is about 861.5429525483.

The spelling of 639485649 in words is "six hundred thirty-nine million, four hundred eighty-five thousand, six hundred forty-nine".