638270020 has 12 divisors (see below), whose sum is σ = 1340367084. Its totient is φ = 255308000.

The previous prime is 638269969. The next prime is 638270041. The reversal of 638270020 is 20072836.

It can be written as a sum of positive squares in 2 ways, for example, as 229340736 + 408929284 = 15144^2 + 20222^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15956731 + ... + 15956770.

It is an arithmetic number, because the mean of its divisors is an integer number (111697257).

Almost surely, 2^638270020 is an apocalyptic number.

It is an amenable number.

638270020 is an abundant number, since it is smaller than the sum of its proper divisors (702097064).

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

638270020 is a wasteful number, since it uses less digits than its factorization.

638270020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31913510 (or 31913508 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 638270020 is about 25264.0064122854. The cubic root of 638270020 is about 860.9966901301.

The spelling of 638270020 in words is "six hundred thirty-eight million, two hundred seventy thousand, twenty".