639761049 has 12 divisors (see below), whose sum is σ = 937115712. Its totient is φ = 420499800.

The previous prime is 639761047. The next prime is 639761053. The reversal of 639761049 is 940167936.

639761049 is a `hidden beast` number, since 639 + 7 + 6 + 1 + 0 + 4 + 9 = 666.

639761049 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 639761049 - 2¹ = 639761047 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 639760995 and 639761013.

It is not an unprimeable number, because it can be changed into a prime (639761041) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 499957 + ... + 501234.

It is an arithmetic number, because the mean of its divisors is an integer number (78092976).

Almost surely, 2^639761049 is an apocalyptic number.

It is an amenable number.

639761049 is a deficient number, since it is larger than the sum of its proper divisors (297354663).

639761049 is a wasteful number, since it uses less digits than its factorization.

639761049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1001268 (or 1001265 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The square root of 639761049 is about 25293.4981566410. The cubic root of 639761049 is about 861.6666117615. Note that the first 4 decimals are identical.

It can be divided in two parts, 63976 and 1049, that added together give a square (65025 = 255²).

The spelling of 639761049 in words is "six hundred thirty-nine million, seven hundred sixty-one thousand, forty-nine".