638315232 has 24 divisors (see below), whose sum is σ = 1675577736. Its totient is φ = 212771712.

The previous prime is 638315179. The next prime is 638315239. The reversal of 638315232 is 232513836.

It is a tau number, because it is divible by the number of its divisors (24).

It is a junction number, because it is equal to n+sod(n) for n = 638315193 and 638315202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638315239) 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, 3324463 + ... + 3324654.

It is an arithmetic number, because the mean of its divisors is an integer number (69815739).

Almost surely, 2^638315232 is an apocalyptic number.

It is an amenable number.

638315232 is an abundant number, since it is smaller than the sum of its proper divisors (1037262504).

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

638315232 is a wasteful number, since it uses less digits than its factorization.

638315232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6649130 (or 6649122 counting only the distinct ones).

The product of its digits is 25920, while the sum is 33.

The square root of 638315232 is about 25264.9011872202. The cubic root of 638315232 is about 861.0170192813.

The spelling of 638315232 in words is "six hundred thirty-eight million, three hundred fifteen thousand, two hundred thirty-two".