20197715581057 has 4 divisors (see below), whose sum is σ = 23083103521216. Its totient is φ = 17312327640900.

The previous prime is 20197715581049. The next prime is 20197715581181. The reversal of 20197715581057 is 75018551779102.

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.

It is a cyclic number.

It is not a de Polignac number, because 20197715581057 - 2³ = 20197715581049 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20197715580992 and 20197715581010.

It is not an unprimeable number, because it can be changed into a prime (20197715381057) 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, 1442693970069 + ... + 1442693970082.

It is an arithmetic number, because the mean of its divisors is an integer number (5770775880304).

Almost surely, 2^{20197715581057} is an apocalyptic number.

It is an amenable number.

20197715581057 is a deficient number, since it is larger than the sum of its proper divisors (2885387940159).

20197715581057 is an equidigital number, since it uses as much as digits as its factorization.

20197715581057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2885387940158.

The product of its (nonzero) digits is 6174000, while the sum is 58.

The spelling of 20197715581057 in words is "twenty trillion, one hundred ninety-seven billion, seven hundred fifteen million, five hundred eighty-one thousand, fifty-seven".