21122112321 has 12 divisors (see below), whose sum is σ = 30637376640. Its totient is φ = 14022488760.

The previous prime is 21122112283. The next prime is 21122112359. The reversal of 21122112321 is 12321122112.

21122112321 is a `hidden beast` number, since 211 + 22 + 112 + 321 = 666.

It is an interprime number because it is at equal distance from previous prime (21122112283) and next prime (21122112359).

It is not a de Polignac number, because 21122112321 - 2²³ = 21113723713 is a prime.

It is a super-2 number, since 2×21122112321² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21122112294 and 21122112303.

It is not an unprimeable number, because it can be changed into a prime (21122112391) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4907685 + ... + 4911986.

It is an arithmetic number, because the mean of its divisors is an integer number (2553114720).

Almost surely, 2^21122112321 is an apocalyptic number.

It is an amenable number.

21122112321 is a deficient number, since it is larger than the sum of its proper divisors (9515264319).

21122112321 is a wasteful number, since it uses less digits than its factorization.

21122112321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9819916 (or 9819913 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

Adding to 21122112321 its reverse (12321122112), we get a palindrome (33443234433).

The spelling of 21122112321 in words is "twenty-one billion, one hundred twenty-two million, one hundred twelve thousand, three hundred twenty-one".