21364223421 has 8 divisors (see below), whose sum is σ = 28486357344. Its totient is φ = 14242452560.

The previous prime is 21364223393. The next prime is 21364223429. The reversal of 21364223421 is 12432246312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21364223421 - 2⁵ = 21364223389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21364223429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 109951 + ... + 234131.

It is an arithmetic number, because the mean of its divisors is an integer number (3560794668).

Almost surely, 2^21364223421 is an apocalyptic number.

It is an amenable number.

21364223421 is a deficient number, since it is larger than the sum of its proper divisors (7122133923).

21364223421 is a wasteful number, since it uses less digits than its factorization.

21364223421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181531.

The product of its digits is 13824, while the sum is 30.

Adding to 21364223421 its reverse (12432246312), we get a palindrome (33796469733).

The spelling of 21364223421 in words is "twenty-one billion, three hundred sixty-four million, two hundred twenty-three thousand, four hundred twenty-one".