18397835520 has 288 divisors, whose sum is σ = 61058629632. Its totient is φ = 4717633536.

The previous prime is 18397835513. The next prime is 18397835581. The reversal of 18397835520 is 2553879381.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11062209 + ... + 11063871.

Almost surely, 2^18397835520 is an apocalyptic number.

18397835520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18397835520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30529314816).

18397835520 is an abundant number, since it is smaller than the sum of its proper divisors (42660794112).

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

18397835520 is a wasteful number, since it uses less digits than its factorization.

18397835520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1797 (or 1783 counting only the distinct ones).

The product of its (nonzero) digits is 1814400, while the sum is 51.

The spelling of 18397835520 in words is "eighteen billion, three hundred ninety-seven million, eight hundred thirty-five thousand, five hundred twenty".