20113568621 has 2 divisors, whose sum is σ = 20113568622. Its totient is φ = 20113568620.

The previous prime is 20113568603. The next prime is 20113568633. The reversal of 20113568621 is 12686531102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20064722500 + 48846121 = 141650^2 + 6989^2 .

It is a cyclic number.

It is not a de Polignac number, because 20113568621 - 2³⁴ = 2933699437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20113568681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10056784310 + 10056784311.

It is an arithmetic number, because the mean of its divisors is an integer number (10056784311).

Almost surely, 2^20113568621 is an apocalyptic number.

It is an amenable number.

20113568621 is a deficient number, since it is larger than the sum of its proper divisors (1).

20113568621 is an equidigital number, since it uses as much as digits as its factorization.

20113568621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17280, while the sum is 35.

The spelling of 20113568621 in words is "twenty billion, one hundred thirteen million, five hundred sixty-eight thousand, six hundred twenty-one".