638775076 has 9 divisors (see below), whose sum is σ = 1117944849. Its totient is φ = 319362264.

The previous prime is 638775047. The next prime is 638775077. The reversal of 638775076 is 670577836.

The square root of 638775076 is 25274.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 61622500 + 577152576 = 7850^2 + 24024^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638775077) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 44230 + ... + 56866.

Almost surely, 2^638775076 is an apocalyptic number.

638775076 is the 25274-th square number.

It is an amenable number.

638775076 is a deficient number, since it is larger than the sum of its proper divisors (479169773).

638775076 is an frugal number, since it uses more digits than its factorization.

638775076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25278 (or 12639 counting only the distinct ones).

The product of its (nonzero) digits is 1481760, while the sum is 49.

The cubic root of 638775076 is about 861.2237293054.

Multiplying 638775076 by its sum of digits (49), we get a square (31299978724 = 176918²).

The spelling of 638775076 in words is "six hundred thirty-eight million, seven hundred seventy-five thousand, seventy-six".