18817461638 has 16 divisors (see below), whose sum is σ = 30009146976. Its totient is φ = 8829849600.

The previous prime is 18817461613. The next prime is 18817461697. The reversal of 18817461638 is 83616471881.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a self number, because there is not a number n which added to its sum of digits gives 18817461638.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3856763 + ... + 3861638.

It is an arithmetic number, because the mean of its divisors is an integer number (1875571686).

Almost surely, 2^18817461638 is an apocalyptic number.

18817461638 is a deficient number, since it is larger than the sum of its proper divisors (11191685338).

18817461638 is a wasteful number, since it uses less digits than its factorization.

18817461638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7718479.

The product of its digits is 1548288, while the sum is 53.

The spelling of 18817461638 in words is "eighteen billion, eight hundred seventeen million, four hundred sixty-one thousand, six hundred thirty-eight".