638900474 has 4 divisors (see below), whose sum is σ = 958350714. Its totient is φ = 319450236.

The previous prime is 638900467. The next prime is 638900489. The reversal of 638900474 is 474009836.

638900474 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 569061025 + 69839449 = 23855^2 + 8357^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 159725117 + ... + 159725120.

Almost surely, 2^638900474 is an apocalyptic number.

638900474 is a deficient number, since it is larger than the sum of its proper divisors (319450240).

638900474 is a wasteful number, since it uses less digits than its factorization.

638900474 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319450239.

The product of its (nonzero) digits is 145152, while the sum is 41.

The square root of 638900474 is about 25276.4806490144. The cubic root of 638900474 is about 861.2800812573.

The spelling of 638900474 in words is "six hundred thirty-eight million, nine hundred thousand, four hundred seventy-four".