21512644131513 has 4 divisors (see below), whose sum is σ = 28683525508688. Its totient is φ = 14341762754340.

The previous prime is 21512644131499. The next prime is 21512644131521. The reversal of 21512644131513 is 31513144621512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21512644131513 - 2⁴ = 21512644131497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21512644131533) 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 3 ways as a sum of consecutive naturals, for example, 3585440688583 + ... + 3585440688588.

It is an arithmetic number, because the mean of its divisors is an integer number (7170881377172).

Almost surely, 2^{21512644131513} is an apocalyptic number.

It is an amenable number.

21512644131513 is a deficient number, since it is larger than the sum of its proper divisors (7170881377175).

21512644131513 is an equidigital number, since it uses as much as digits as its factorization.

21512644131513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7170881377174.

The product of its digits is 86400, while the sum is 39.

The spelling of 21512644131513 in words is "twenty-one trillion, five hundred twelve billion, six hundred forty-four million, one hundred thirty-one thousand, five hundred thirteen".