18640372 has 6 divisors (see below), whose sum is σ = 32620658. Its totient is φ = 9320184.

The previous prime is 18640351. The next prime is 18640399. The reversal of 18640372 is 27304681.

It can be written as a sum of positive squares in only one way, i.e., 11532816 + 7107556 = 3396^2 + 2666^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2330043 + ... + 2330050.

Almost surely, 2^18640372 is an apocalyptic number.

It is an amenable number.

18640372 is a deficient number, since it is larger than the sum of its proper divisors (13980286).

18640372 is a wasteful number, since it uses less digits than its factorization.

18640372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4660097 (or 4660095 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 18640372 is about 4317.4497101877. The cubic root of 18640372 is about 265.1458648726.

The spelling of 18640372 in words is "eighteen million, six hundred forty thousand, three hundred seventy-two".