638104780 has 12 divisors (see below), whose sum is σ = 1340020080. Its totient is φ = 255241904.

The previous prime is 638104757. The next prime is 638104781. The reversal of 638104780 is 87401836.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (638104781) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15952600 + ... + 15952639.

It is an arithmetic number, because the mean of its divisors is an integer number (111668340).

Almost surely, 2^638104780 is an apocalyptic number.

It is an amenable number.

638104780 is an abundant number, since it is smaller than the sum of its proper divisors (701915300).

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

638104780 is a wasteful number, since it uses less digits than its factorization.

638104780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31905248 (or 31905246 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 37.

The square root of 638104780 is about 25260.7359354394. The cubic root of 638104780 is about 860.9223833488.

The spelling of 638104780 in words is "six hundred thirty-eight million, one hundred four thousand, seven hundred eighty".