638372571652 has 6 divisors (see below), whose sum is σ = 1117152000398. Its totient is φ = 319186285824.

The previous prime is 638372571607. The next prime is 638372571731. The reversal of 638372571652 is 256175273836.

It can be written as a sum of positive squares in only one way, i.e., 517919151556 + 120453420096 = 719666^2 + 347064^2 .

It is a junction number, because it is equal to n+sod(n) for n = 638372571593 and 638372571602.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79796571453 + ... + 79796571460.

Almost surely, 2^638372571652 is an apocalyptic number.

It is an amenable number.

638372571652 is a deficient number, since it is larger than the sum of its proper divisors (478779428746).

638372571652 is a wasteful number, since it uses less digits than its factorization.

638372571652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159593142917 (or 159593142915 counting only the distinct ones).

The product of its digits is 12700800, while the sum is 55.

The spelling of 638372571652 in words is "six hundred thirty-eight billion, three hundred seventy-two million, five hundred seventy-one thousand, six hundred fifty-two".