18360021421 has 16 divisors (see below), whose sum is σ = 21320513280. Its totient is φ = 15484815360.

The previous prime is 18360021389. The next prime is 18360021443. The reversal of 18360021421 is 12412006381.

It is not a de Polignac number, because 18360021421 - 2⁵ = 18360021389 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18360021421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18360021451) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 216685 + ... + 289261.

It is an arithmetic number, because the mean of its divisors is an integer number (1332532080).

Almost surely, 2^18360021421 is an apocalyptic number.

It is an amenable number.

18360021421 is a deficient number, since it is larger than the sum of its proper divisors (2960491859).

18360021421 is an equidigital number, since it uses as much as digits as its factorization.

18360021421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73164.

The product of its (nonzero) digits is 2304, while the sum is 28.

The spelling of 18360021421 in words is "eighteen billion, three hundred sixty million, twenty-one thousand, four hundred twenty-one".