639237029537 has 4 divisors (see below), whose sum is σ = 651298105620. Its totient is φ = 627175953456.

The previous prime is 639237029513. The next prime is 639237029549. The reversal of 639237029537 is 735920732936.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 287820447121 + 351416582416 = 536489^2 + 592804^2 .

It is a cyclic number.

It is not a de Polignac number, because 639237029537 - 2²² = 639232835233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (639237029507) 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, 6030537962 + ... + 6030538067.

It is an arithmetic number, because the mean of its divisors is an integer number (162824526405).

Almost surely, 2^639237029537 is an apocalyptic number.

It is an amenable number.

639237029537 is a deficient number, since it is larger than the sum of its proper divisors (12061076083).

639237029537 is a wasteful number, since it uses less digits than its factorization.

639237029537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12061076082.

The product of its (nonzero) digits is 12859560, while the sum is 56.

The spelling of 639237029537 in words is "six hundred thirty-nine billion, two hundred thirty-seven million, twenty-nine thousand, five hundred thirty-seven".