21312222330021 has 16 divisors (see below), whose sum is σ = 32475894232704. Its totient is φ = 12178365182784.

The previous prime is 21312222329927. The next prime is 21312222330089. The reversal of 21312222330021 is 12003322221312.

It is not a de Polignac number, because 21312222330021 - 2¹⁰ = 21312222328997 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21312222329973 and 21312222330000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21312222330121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3931255 + ... + 7620971.

It is an arithmetic number, because the mean of its divisors is an integer number (2029743389544).

Almost surely, 2^{21312222330021} is an apocalyptic number.

21312222330021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21312222330021 is a deficient number, since it is larger than the sum of its proper divisors (11163671902683).

21312222330021 is a wasteful number, since it uses less digits than its factorization.

21312222330021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3964780.

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

Adding to 21312222330021 its reverse (12003322221312), we get a palindrome (33315544551333).

The spelling of 21312222330021 in words is "twenty-one trillion, three hundred twelve billion, two hundred twenty-two million, three hundred thirty thousand, twenty-one".