21512846713 has 2 divisors, whose sum is σ = 21512846714. Its totient is φ = 21512846712.

The previous prime is 21512846699. The next prime is 21512846717. The reversal of 21512846713 is 31764821512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21455511529 + 57335184 = 146477^2 + 7572^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21512846713 is a prime.

It is not a weakly prime, because it can be changed into another prime (21512846717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10756423356 + 10756423357.

It is an arithmetic number, because the mean of its divisors is an integer number (10756423357).

Almost surely, 2^21512846713 is an apocalyptic number.

It is an amenable number.

21512846713 is a deficient number, since it is larger than the sum of its proper divisors (1).

21512846713 is an equidigital number, since it uses as much as digits as its factorization.

21512846713 is an evil number, because the sum of its binary digits is even.

The product of its digits is 80640, while the sum is 40.

The spelling of 21512846713 in words is "twenty-one billion, five hundred twelve million, eight hundred forty-six thousand, seven hundred thirteen".