166077902021 has 2 divisors, whose sum is σ = 166077902022. Its totient is φ = 166077902020.

The previous prime is 166077901973. The next prime is 166077902041. The reversal of 166077902021 is 120209770661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 125961817921 + 40116084100 = 354911^2 + 200290^2 .

It is a cyclic number.

It is not a de Polignac number, because 166077902021 - 2³⁰ = 165004160197 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 166077902021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166077902041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83038951010 + 83038951011.

It is an arithmetic number, because the mean of its divisors is an integer number (83038951011).

Almost surely, 2^166077902021 is an apocalyptic number.

It is an amenable number.

166077902021 is a deficient number, since it is larger than the sum of its proper divisors (1).

166077902021 is an equidigital number, since it uses as much as digits as its factorization.

166077902021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 63504, while the sum is 41.

The spelling of 166077902021 in words is "one hundred sixty-six billion, seventy-seven million, nine hundred two thousand, twenty-one".