166265641 has 2 divisors, whose sum is σ = 166265642. Its totient is φ = 166265640.

The previous prime is 166265639. The next prime is 166265651. The reversal of 166265641 is 146562661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112975641 + 53290000 = 10629^2 + 7300^2 .

It is a cyclic number.

It is not a de Polignac number, because 166265641 - 2¹ = 166265639 is a prime.

Together with 166265639, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 166265641.

It is not a weakly prime, because it can be changed into another prime (166265621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83132820 + 83132821.

It is an arithmetic number, because the mean of its divisors is an integer number (83132821).

Almost surely, 2^166265641 is an apocalyptic number.

It is an amenable number.

166265641 is a deficient number, since it is larger than the sum of its proper divisors (1).

166265641 is an equidigital number, since it uses as much as digits as its factorization.

166265641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 37.

The square root of 166265641 is about 12894.4034759271. The cubic root of 166265641 is about 549.8794678022.

The spelling of 166265641 in words is "one hundred sixty-six million, two hundred sixty-five thousand, six hundred forty-one".