166107016715021 has 4 divisors (see below), whose sum is σ = 166143531781500. Its totient is φ = 166070501648544.

The previous prime is 166107016715009. The next prime is 166107016715027. The reversal of 166107016715021 is 120517610701661.

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 66178403970121 + 99928612744900 = 8135011^2 + 9996430^2 .

It is a cyclic number.

It is not a de Polignac number, because 166107016715021 - 2¹⁰ = 166107016713997 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 (166107016715027) 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, 18257526416 + ... + 18257535513.

It is an arithmetic number, because the mean of its divisors is an integer number (41535882945375).

Almost surely, 2^{166107016715021} is an apocalyptic number.

It is an amenable number.

166107016715021 is a deficient number, since it is larger than the sum of its proper divisors (36515066479).

166107016715021 is an equidigital number, since it uses as much as digits as its factorization.

166107016715021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36515066478.

The product of its (nonzero) digits is 105840, while the sum is 44.

The spelling of 166107016715021 in words is "one hundred sixty-six trillion, one hundred seven billion, sixteen million, seven hundred fifteen thousand, twenty-one".