638367268 has 48 divisors (see below), whose sum is σ = 1406659968. Its totient is φ = 246240000.

The previous prime is 638367259. The next prime is 638367281. The reversal of 638367268 is 862763836.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20848 + ... + 41368.

It is an arithmetic number, because the mean of its divisors is an integer number (29305416).

Almost surely, 2^638367268 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638367268, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (703329984).

638367268 is an abundant number, since it is smaller than the sum of its proper divisors (768292700).

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

638367268 is a wasteful number, since it uses less digits than its factorization.

638367268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20644 (or 20642 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 49.

The square root of 638367268 is about 25265.9309743378. The cubic root of 638367268 is about 861.0404155918.

The spelling of 638367268 in words is "six hundred thirty-eight million, three hundred sixty-seven thousand, two hundred sixty-eight".