21031022013013 has 4 divisors (see below), whose sum is σ = 21040274554668. Its totient is φ = 21021769471360.

The previous prime is 21031022012953. The next prime is 21031022013019. The reversal of 21031022013013 is 31031022013012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10321942477284 + 10709079535729 = 3212778^2 + 3272473^2 .

It is a cyclic number.

It is not a de Polignac number, because 21031022013013 - 2²¹ = 21031019915861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031022013019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4626267418 + ... + 4626271963.

It is an arithmetic number, because the mean of its divisors is an integer number (5260068638667).

Almost surely, 2^{21031022013013} is an apocalyptic number.

It is an amenable number.

21031022013013 is a deficient number, since it is larger than the sum of its proper divisors (9252541655).

21031022013013 is an equidigital number, since it uses as much as digits as its factorization.

21031022013013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9252541654.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21031022013013 its reverse (31031022013012), we get a palindrome (52062044026025).

Subtracting 21031022013013 from its reverse (31031022013012), we obtain a palindrome (9999999999999).

The spelling of 21031022013013 in words is "twenty-one trillion, thirty-one billion, twenty-two million, thirteen thousand, thirteen".