201220021957 has 2 divisors, whose sum is σ = 201220021958. Its totient is φ = 201220021956.

The previous prime is 201220021921. The next prime is 201220022009. The reversal of 201220021957 is 759120022102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 132491632036 + 68728389921 = 363994^2 + 262161^2 .

It is a cyclic number.

It is not a de Polignac number, because 201220021957 - 2¹⁵ = 201219989189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201220021157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100610010978 + 100610010979.

It is an arithmetic number, because the mean of its divisors is an integer number (100610010979).

Almost surely, 2^201220021957 is an apocalyptic number.

It is an amenable number.

201220021957 is a deficient number, since it is larger than the sum of its proper divisors (1).

201220021957 is an equidigital number, since it uses as much as digits as its factorization.

201220021957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5040, while the sum is 31.

The spelling of 201220021957 in words is "two hundred one billion, two hundred twenty million, twenty-one thousand, nine hundred fifty-seven".