20210120021057 has 2 divisors, whose sum is σ = 20210120021058. Its totient is φ = 20210120021056.

The previous prime is 20210120020997. The next prime is 20210120021111. The reversal of 20210120021057 is 75012002101202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20101377703936 + 108742317121 = 4483456^2 + 329761^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20210120021057 is a prime.

It is not a weakly prime, because it can be changed into another prime (20210120027057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105060010528 + 10105060010529.

It is an arithmetic number, because the mean of its divisors is an integer number (10105060010529).

Almost surely, 2^{20210120021057} is an apocalyptic number.

It is an amenable number.

20210120021057 is a deficient number, since it is larger than the sum of its proper divisors (1).

20210120021057 is an equidigital number, since it uses as much as digits as its factorization.

20210120021057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 560, while the sum is 23.

Adding to 20210120021057 its reverse (75012002101202), we get a palindrome (95222122122259).

The spelling of 20210120021057 in words is "twenty trillion, two hundred ten billion, one hundred twenty million, twenty-one thousand, fifty-seven".