166021564202957 has 2 divisors, whose sum is σ = 166021564202958. Its totient is φ = 166021564202956.

The previous prime is 166021564202869. The next prime is 166021564202983. The reversal of 166021564202957 is 759202465120661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120475451729161 + 45546112473796 = 10976131^2 + 6748786^2 .

It is a cyclic number.

It is not a de Polignac number, because 166021564202957 - 2³⁴ = 166004384333773 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166021564232957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83010782101478 + 83010782101479.

It is an arithmetic number, because the mean of its divisors is an integer number (83010782101479).

Almost surely, 2^{166021564202957} is an apocalyptic number.

It is an amenable number.

166021564202957 is a deficient number, since it is larger than the sum of its proper divisors (1).

166021564202957 is an equidigital number, since it uses as much as digits as its factorization.

166021564202957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10886400, while the sum is 56.

The spelling of 166021564202957 in words is "one hundred sixty-six trillion, twenty-one billion, five hundred sixty-four million, two hundred two thousand, nine hundred fifty-seven".