201997973 has 2 divisors, whose sum is σ = 201997974. Its totient is φ = 201997972.

The previous prime is 201997951. The next prime is 201998011. The reversal of 201997973 is 379799102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 114425809 + 87572164 = 10697^2 + 9358^2 .

It is a cyclic number.

It is not a de Polignac number, because 201997973 - 2⁶ = 201997909 is a prime.

It is a super-2 number, since 2×201997973² = 81606362192217458, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201997073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100998986 + 100998987.

It is an arithmetic number, because the mean of its divisors is an integer number (100998987).

Almost surely, 2^201997973 is an apocalyptic number.

It is an amenable number.

201997973 is a deficient number, since it is larger than the sum of its proper divisors (1).

201997973 is an equidigital number, since it uses as much as digits as its factorization.

201997973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 214326, while the sum is 47.

The square root of 201997973 is about 14212.5990937618. The cubic root of 201997973 is about 586.7444682387.

The spelling of 201997973 in words is "two hundred one million, nine hundred ninety-seven thousand, nine hundred seventy-three".