21620663007613 has 16 divisors (see below), whose sum is σ = 22245418509120. Its totient is φ = 20998039176576.

The previous prime is 21620663007577. The next prime is 21620663007631. The reversal of 21620663007613 is 31670036602612.

It is a cyclic number.

It is not a de Polignac number, because 21620663007613 - 2²⁹ = 21620126136701 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21620663007613.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21620663007113) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 659089870 + ... + 659122672.

It is an arithmetic number, because the mean of its divisors is an integer number (1390338656820).

Almost surely, 2^{21620663007613} is an apocalyptic number.

It is an amenable number.

21620663007613 is a deficient number, since it is larger than the sum of its proper divisors (624755501507).

21620663007613 is a wasteful number, since it uses less digits than its factorization.

21620663007613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64716.

The product of its (nonzero) digits is 326592, while the sum is 43.

The spelling of 21620663007613 in words is "twenty-one trillion, six hundred twenty billion, six hundred sixty-three million, seven thousand, six hundred thirteen".