639271420 has 24 divisors (see below), whose sum is σ = 1355766048. Its totient is φ = 253176000.

The previous prime is 639271379. The next prime is 639271421. The reversal of 639271420 is 24172936.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639271421) 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, 156216 + ... + 160255.

It is an arithmetic number, because the mean of its divisors is an integer number (56490252).

Almost surely, 2^639271420 is an apocalyptic number.

It is an amenable number.

639271420 is an abundant number, since it is smaller than the sum of its proper divisors (716494628).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639271420 is a wasteful number, since it uses less digits than its factorization.

639271420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316581 (or 316579 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 639271420 is about 25283.8173541892. The cubic root of 639271420 is about 861.4467355862.

The spelling of 639271420 in words is "six hundred thirty-nine million, two hundred seventy-one thousand, four hundred twenty".