20557060784417 has 4 divisors (see below), whose sum is σ = 20557070122176. Its totient is φ = 20557051446660.

The previous prime is 20557060784401. The next prime is 20557060784443. The reversal of 20557060784417 is 71448706075502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20557060784417 - 2⁴ = 20557060784401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20557060786417) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 663188 + ... + 6446234.

It is an arithmetic number, because the mean of its divisors is an integer number (5139267530544).

Almost surely, 2^{20557060784417} is an apocalyptic number.

It is an amenable number.

20557060784417 is a deficient number, since it is larger than the sum of its proper divisors (9337759).

20557060784417 is an equidigital number, since it uses as much as digits as its factorization.

20557060784417 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9337758.

The product of its (nonzero) digits is 13171200, while the sum is 56.

The spelling of 20557060784417 in words is "twenty trillion, five hundred fifty-seven billion, sixty million, seven hundred eighty-four thousand, four hundred seventeen".