166021564203013 has 4 divisors (see below), whose sum is σ = 168295832205868. Its totient is φ = 163747296200160.

The previous prime is 166021564202983. The next prime is 166021564203017. The reversal of 166021564203013 is 310302465120661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 101106202404964 + 64915361798049 = 10055158^2 + 8057007^2 .

It is a cyclic number.

It is not a de Polignac number, because 166021564203013 - 2²⁹ = 166021027332101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166021564203017) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1137134001318 + ... + 1137134001463.

It is an arithmetic number, because the mean of its divisors is an integer number (42073958051467).

Almost surely, 2^{166021564203013} is an apocalyptic number.

It is an amenable number.

166021564203013 is a deficient number, since it is larger than the sum of its proper divisors (2274268002855).

166021564203013 is an equidigital number, since it uses as much as digits as its factorization.

166021564203013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2274268002854.

The product of its (nonzero) digits is 155520, while the sum is 40.

The spelling of 166021564203013 in words is "one hundred sixty-six trillion, twenty-one billion, five hundred sixty-four million, two hundred three thousand, thirteen".