21311224679 has 4 divisors (see below), whose sum is σ = 21660589080. Its totient is φ = 20961860280.

The previous prime is 21311224673. The next prime is 21311224699. The reversal of 21311224679 is 97642211312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21311224679 - 2⁸ = 21311224423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21311224673) 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, 174682109 + ... + 174682230.

It is an arithmetic number, because the mean of its divisors is an integer number (5415147270).

Almost surely, 2^21311224679 is an apocalyptic number.

21311224679 is a deficient number, since it is larger than the sum of its proper divisors (349364401).

21311224679 is an equidigital number, since it uses as much as digits as its factorization.

21311224679 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 349364400.

The product of its digits is 36288, while the sum is 38.

The spelling of 21311224679 in words is "twenty-one billion, three hundred eleven million, two hundred twenty-four thousand, six hundred seventy-nine".