21021230313 has 12 divisors (see below), whose sum is σ = 30861770628. Its totient is φ = 13784412960.

The previous prime is 21021230287. The next prime is 21021230323. The reversal of 21021230313 is 31303212012.

It can be written as a sum of positive squares in 2 ways, for example, as 684188649 + 20337041664 = 26157^2 + 142608^2 .

It is not a de Polignac number, because 21021230313 - 2⁶ = 21021230249 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21021230323) 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, 19144470 + ... + 19145567.

It is an arithmetic number, because the mean of its divisors is an integer number (2571814219).

Almost surely, 2^21021230313 is an apocalyptic number.

It is an amenable number.

21021230313 is a deficient number, since it is larger than the sum of its proper divisors (9840540315).

21021230313 is a wasteful number, since it uses less digits than its factorization.

21021230313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38290104 (or 38290101 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21021230313 its reverse (31303212012), we get a palindrome (52324442325).

The spelling of 21021230313 in words is "twenty-one billion, twenty-one million, two hundred thirty thousand, three hundred thirteen".