21321313404 has 12 divisors (see below), whose sum is σ = 49749731304. Its totient is φ = 7107104464.

The previous prime is 21321313399. The next prime is 21321313411. The reversal of 21321313404 is 40431312312.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 888388047 + ... + 888388070.

It is an arithmetic number, because the mean of its divisors is an integer number (4145810942).

Almost surely, 2^21321313404 is an apocalyptic number.

It is an amenable number.

21321313404 is an abundant number, since it is smaller than the sum of its proper divisors (28428417900).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21321313404 is a wasteful number, since it uses less digits than its factorization.

21321313404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1776776124 (or 1776776122 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 21321313404 its reverse (40431312312), we get a palindrome (61752625716).

The spelling of 21321313404 in words is "twenty-one billion, three hundred twenty-one million, three hundred thirteen thousand, four hundred four".