21197418353 has 4 divisors (see below), whose sum is σ = 21286110720. Its totient is φ = 21108725988.

The previous prime is 21197418313. The next prime is 21197418377. The reversal of 21197418353 is 35381479112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21197418353 - 2²⁶ = 21130309489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21197418313) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44345825 + ... + 44346302.

It is an arithmetic number, because the mean of its divisors is an integer number (5321527680).

Almost surely, 2^21197418353 is an apocalyptic number.

It is an amenable number.

21197418353 is a deficient number, since it is larger than the sum of its proper divisors (88692367).

21197418353 is an equidigital number, since it uses as much as digits as its factorization.

21197418353 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88692366.

The product of its digits is 181440, while the sum is 44.

The spelling of 21197418353 in words is "twenty-one billion, one hundred ninety-seven million, four hundred eighteen thousand, three hundred fifty-three".