18266999581974 has 128 divisors (see below), whose sum is σ = 43541317403136. Its totient is φ = 5078297980800.

The previous prime is 18266999581889. The next prime is 18266999582033. The reversal of 18266999581974 is 47918599966281.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 16382604 + ... + 17462064.

It is an arithmetic number, because the mean of its divisors is an integer number (340166542212).

Almost surely, 2^{18266999581974} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18266999581974, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21770658701568).

18266999581974 is an abundant number, since it is smaller than the sum of its proper divisors (25274317821162).

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

18266999581974 is a wasteful number, since it uses less digits than its factorization.

18266999581974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1079675 (or 1079653 counting only the distinct ones).

The product of its digits is 4232632320, while the sum is 84.

The spelling of 18266999581974 in words is "eighteen trillion, two hundred sixty-six billion, nine hundred ninety-nine million, five hundred eighty-one thousand, nine hundred seventy-four".