21002131231013 has 16 divisors (see below), whose sum is σ = 21799398481920. Its totient is φ = 20220318004656.

The previous prime is 21002131230973. The next prime is 21002131231051. The reversal of 21002131231013 is 31013213120012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21002131231013 - 2³⁸ = 20727253324069 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 (21002131231093) 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 15 ways as a sum of consecutive naturals, for example, 2373881 + ... + 6902142.

It is an arithmetic number, because the mean of its divisors is an integer number (1362462405120).

Almost surely, 2^{21002131231013} is an apocalyptic number.

It is an amenable number.

21002131231013 is a deficient number, since it is larger than the sum of its proper divisors (797267250907).

21002131231013 is an equidigital number, since it uses as much as digits as its factorization.

21002131231013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9276856.

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 21002131231013 its reverse (31013213120012), we get a palindrome (52015344351025).

The spelling of 21002131231013 in words is "twenty-one trillion, two billion, one hundred thirty-one million, two hundred thirty-one thousand, thirteen".