639923983 has 2 divisors, whose sum is σ = 639923984. Its totient is φ = 639923982.

The previous prime is 639923969. The next prime is 639923987. The reversal of 639923983 is 389329936.

639923983 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 639923983 - 2⁵ = 639923951 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 639923983.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (639923987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319961991 + 319961992.

It is an arithmetic number, because the mean of its divisors is an integer number (319961992).

Almost surely, 2^639923983 is an apocalyptic number.

639923983 is a deficient number, since it is larger than the sum of its proper divisors (1).

639923983 is an equidigital number, since it uses as much as digits as its factorization.

639923983 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1889568, while the sum is 52.

The square root of 639923983 is about 25296.7188188508. The cubic root of 639923983 is about 861.7397551489.

The spelling of 639923983 in words is "six hundred thirty-nine million, nine hundred twenty-three thousand, nine hundred eighty-three".