21125829713 has 2 divisors, whose sum is σ = 21125829714. Its totient is φ = 21125829712.

The previous prime is 21125829709. The next prime is 21125829719. The reversal of 21125829713 is 31792852112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18472343569 + 2653486144 = 135913^2 + 51512^2 .

It is a cyclic number.

It is not a de Polignac number, because 21125829713 - 2² = 21125829709 is a prime.

It is not a weakly prime, because it can be changed into another prime (21125829719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10562914856 + 10562914857.

It is an arithmetic number, because the mean of its divisors is an integer number (10562914857).

Almost surely, 2^21125829713 is an apocalyptic number.

It is an amenable number.

21125829713 is a deficient number, since it is larger than the sum of its proper divisors (1).

21125829713 is an equidigital number, since it uses as much as digits as its factorization.

21125829713 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 41.

The spelling of 21125829713 in words is "twenty-one billion, one hundred twenty-five million, eight hundred twenty-nine thousand, seven hundred thirteen".