21221314399 has 4 divisors (see below), whose sum is σ = 21905872960. Its totient is φ = 20536755840.

The previous prime is 21221314379. The next prime is 21221314409. The reversal of 21221314399 is 99341312212.

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 21221314399 - 2⁹ = 21221313887 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 (21221314349) 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, 342279234 + ... + 342279295.

It is an arithmetic number, because the mean of its divisors is an integer number (5476468240).

Almost surely, 2^21221314399 is an apocalyptic number.

21221314399 is a deficient number, since it is larger than the sum of its proper divisors (684558561).

21221314399 is an equidigital number, since it uses as much as digits as its factorization.

21221314399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 684558560.

The product of its digits is 23328, while the sum is 37.

The spelling of 21221314399 in words is "twenty-one billion, two hundred twenty-one million, three hundred fourteen thousand, three hundred ninety-nine".