639459643537 has 24 divisors (see below), whose sum is σ = 768184253280. Its totient is φ = 527514324480.

The previous prime is 639459643517. The next prime is 639459643549. The reversal of 639459643537 is 735346954936.

It is a happy number.

It is not a de Polignac number, because 639459643537 - 2⁷ = 639459643409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (639459643517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2805408 + ... + 3024769.

It is an arithmetic number, because the mean of its divisors is an integer number (32007677220).

Almost surely, 2^639459643537 is an apocalyptic number.

It is an amenable number.

639459643537 is a deficient number, since it is larger than the sum of its proper divisors (128724609743).

639459643537 is a wasteful number, since it uses less digits than its factorization.

639459643537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5830273 (or 5830260 counting only the distinct ones).

The product of its digits is 220449600, while the sum is 64.

The spelling of 639459643537 in words is "six hundred thirty-nine billion, four hundred fifty-nine million, six hundred forty-three thousand, five hundred thirty-seven".