21221312130 has 24 divisors (see below), whose sum is σ = 55175411772. Its totient is φ = 5659016544.

The previous prime is 21221312087. The next prime is 21221312153. The reversal of 21221312130 is 3121312212.

21221312130 is a `hidden beast` number, since 2 + 1 + 221 + 312 + 130 = 666.

21221312130 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 20995140609 + 226171521 = 144897^2 + 15039^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 117896089 + ... + 117896268.

Almost surely, 2^21221312130 is an apocalyptic number.

21221312130 is an abundant number, since it is smaller than the sum of its proper divisors (33954099642).

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

21221312130 is a wasteful number, since it uses less digits than its factorization.

21221312130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235792370 (or 235792367 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21221312130 its reverse (3121312212), we get a palindrome (24342624342).

The spelling of 21221312130 in words is "twenty-one billion, two hundred twenty-one million, three hundred twelve thousand, one hundred thirty".