166268621 has 2 divisors, whose sum is σ = 166268622. Its totient is φ = 166268620.

The previous prime is 166268617. The next prime is 166268651. The reversal of 166268621 is 126862661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 159112996 + 7155625 = 12614^2 + 2675^2 .

It is an emirp because it is prime and its reverse (126862661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166268621 - 2² = 166268617 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166268611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83134310 + 83134311.

It is an arithmetic number, because the mean of its divisors is an integer number (83134311).

Almost surely, 2^166268621 is an apocalyptic number.

It is an amenable number.

166268621 is a deficient number, since it is larger than the sum of its proper divisors (1).

166268621 is an equidigital number, since it uses as much as digits as its factorization.

166268621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 38.

The square root of 166268621 is about 12894.5190294171. The cubic root of 166268621 is about 549.8827529689.

The spelling of 166268621 in words is "one hundred sixty-six million, two hundred sixty-eight thousand, six hundred twenty-one".