639012542 has 16 divisors (see below), whose sum is σ = 1143078912. Its totient is φ = 261955320.

The previous prime is 639012529. The next prime is 639012547. The reversal of 639012542 is 245210936.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 639012499 and 639012508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639012547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 991934 + ... + 992577.

It is an arithmetic number, because the mean of its divisors is an integer number (71442432).

Almost surely, 2^639012542 is an apocalyptic number.

639012542 is a deficient number, since it is larger than the sum of its proper divisors (504066370).

639012542 is a wasteful number, since it uses less digits than its factorization.

639012542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1984543.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 639012542 is about 25278.6973952378. The cubic root of 639012542 is about 861.3304366711.

The spelling of 639012542 in words is "six hundred thirty-nine million, twelve thousand, five hundred forty-two".