638197912 has 24 divisors (see below), whose sum is σ = 1305889740. Its totient is φ = 289982240.

The previous prime is 638197883. The next prime is 638197919. The reversal of 638197912 is 219791836.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638197919) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 235638 + ... + 238330.

Almost surely, 2^638197912 is an apocalyptic number.

It is an amenable number.

638197912 is an abundant number, since it is smaller than the sum of its proper divisors (667691828).

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

638197912 is an equidigital number, since it uses as much as digits as its factorization.

638197912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5403 (or 2706 counting only the distinct ones).

The product of its digits is 163296, while the sum is 46.

The square root of 638197912 is about 25262.5792824090. The cubic root of 638197912 is about 860.9642654584.

The spelling of 638197912 in words is "six hundred thirty-eight million, one hundred ninety-seven thousand, nine hundred twelve".