20513544261617 has 16 divisors (see below), whose sum is σ = 22620921026112. Its totient is φ = 18447100576320.

The previous prime is 20513544261599. The next prime is 20513544261659. The reversal of 20513544261617 is 71616244531502.

It is a cyclic number.

It is not a de Polignac number, because 20513544261617 - 2⁸ = 20513544261361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20513544261677) 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, 12075158 + ... + 13668815.

It is an arithmetic number, because the mean of its divisors is an integer number (1413807564132).

Almost surely, 2^{20513544261617} is an apocalyptic number.

It is an amenable number.

20513544261617 is a deficient number, since it is larger than the sum of its proper divisors (2107376764495).

20513544261617 is a wasteful number, since it uses less digits than its factorization.

20513544261617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25744768.

The product of its (nonzero) digits is 1209600, while the sum is 47.

The spelling of 20513544261617 in words is "twenty trillion, five hundred thirteen billion, five hundred forty-four million, two hundred sixty-one thousand, six hundred seventeen".