18401960640 has 112 divisors (see below), whose sum is σ = 66772852992. Its totient is φ = 4206160896.

The previous prime is 18401960611. The next prime is 18401960653. The reversal of 18401960640 is 4606910481.

It is a tau number, because it is divible by the number of its divisors (112).

It is a super-2 number, since 2×18401960640² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1362474 + ... + 1375913.

Almost surely, 2^18401960640 is an apocalyptic number.

18401960640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18401960640 is an abundant number, since it is smaller than the sum of its proper divisors (48370892352).

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

18401960640 is a wasteful number, since it uses less digits than its factorization.

18401960640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2738414 (or 2738404 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 39.

The spelling of 18401960640 in words is "eighteen billion, four hundred one million, nine hundred sixty thousand, six hundred forty".