20197558057 has 2 divisors, whose sum is σ = 20197558058. Its totient is φ = 20197558056.

The previous prime is 20197558013. The next prime is 20197558081. The reversal of 20197558057 is 75085579102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17679425296 + 2518132761 = 132964^2 + 50181^2 .

It is a cyclic number.

It is not a de Polignac number, because 20197558057 - 2¹¹ = 20197556009 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20197558057.

It is not a weakly prime, because it can be changed into another prime (20197558357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10098779028 + 10098779029.

It is an arithmetic number, because the mean of its divisors is an integer number (10098779029).

Almost surely, 2^20197558057 is an apocalyptic number.

It is an amenable number.

20197558057 is a deficient number, since it is larger than the sum of its proper divisors (1).

20197558057 is an equidigital number, since it uses as much as digits as its factorization.

20197558057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 882000, while the sum is 49.

The spelling of 20197558057 in words is "twenty billion, one hundred ninety-seven million, five hundred fifty-eight thousand, fifty-seven".