21021230031313 has 16 divisors (see below), whose sum is σ = 21708439227216. Its totient is φ = 20342877788160.

The previous prime is 21021230031287. The next prime is 21021230031317. The reversal of 21021230031313 is 31313003212012.

It can be written as a sum of positive squares in 8 ways, for example, as 5484294208449 + 15536935822864 = 2341857^2 + 3941692^2 .

It is a cyclic number.

It is not a de Polignac number, because 21021230031313 - 2¹⁷ = 21021229900241 is a prime.

It is a super-2 number, since 2×21021230031313² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21021230031317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 350970 + ... + 6493507.

It is an arithmetic number, because the mean of its divisors is an integer number (1356777451701).

Almost surely, 2^{21021230031313} is an apocalyptic number.

It is an amenable number.

21021230031313 is a deficient number, since it is larger than the sum of its proper divisors (687209195903).

21021230031313 is a wasteful number, since it uses less digits than its factorization.

21021230031313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6845124.

The product of its (nonzero) digits is 648, while the sum is 22.

Adding to 21021230031313 its reverse (31313003212012), we get a palindrome (52334233243325).

The spelling of 21021230031313 in words is "twenty-one trillion, twenty-one billion, two hundred thirty million, thirty-one thousand, three hundred thirteen".