21101313321 has 20 divisors (see below), whose sum is σ = 34387326864. Its totient is φ = 12788674200.

The previous prime is 21101313319. The next prime is 21101313323. The reversal of 21101313321 is 12331310112.

21101313321 is a `hidden beast` number, since 21 + 10 + 1 + 313 + 321 = 666.

It is an interprime number because it is at equal distance from previous prime (21101313319) and next prime (21101313323).

It is not a de Polignac number, because 21101313321 - 2¹ = 21101313319 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21101313294 and 21101313303.

It is not an unprimeable number, because it can be changed into a prime (21101313323) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 11840475 + ... + 11842256.

Almost surely, 2^21101313321 is an apocalyptic number.

It is an amenable number.

21101313321 is a deficient number, since it is larger than the sum of its proper divisors (13286013543).

21101313321 is a wasteful number, since it uses less digits than its factorization.

21101313321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23682754 (or 23682745 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21101313321 its reverse (12331310112), we get a palindrome (33432623433).

The spelling of 21101313321 in words is "twenty-one billion, one hundred one million, three hundred thirteen thousand, three hundred twenty-one".