18915635980 has 24 divisors (see below), whose sum is σ = 40568004288. Its totient is φ = 7405269888.

The previous prime is 18915635969. The next prime is 18915635989. The reversal of 18915635980 is 8953651981.

It is not an unprimeable number, because it can be changed into a prime (18915635989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10060569 + ... + 10062448.

It is an arithmetic number, because the mean of its divisors is an integer number (1690333512).

Almost surely, 2^18915635980 is an apocalyptic number.

18915635980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18915635980 is an abundant number, since it is smaller than the sum of its proper divisors (21652368308).

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

18915635980 is a wasteful number, since it uses less digits than its factorization.

18915635980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20123073 (or 20123071 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 55.

The spelling of 18915635980 in words is "eighteen billion, nine hundred fifteen million, six hundred thirty-five thousand, nine hundred eighty".