166382591 has 2 divisors, whose sum is σ = 166382592. Its totient is φ = 166382590.

The previous prime is 166382501. The next prime is 166382603. The reversal of 166382591 is 195283661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 166382591 - 2²² = 162188287 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 (166382501) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83191295 + 83191296.

It is an arithmetic number, because the mean of its divisors is an integer number (83191296).

Almost surely, 2^166382591 is an apocalyptic number.

166382591 is a deficient number, since it is larger than the sum of its proper divisors (1).

166382591 is an equidigital number, since it uses as much as digits as its factorization.

166382591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 77760, while the sum is 41.

The square root of 166382591 is about 12898.9375919104. The cubic root of 166382591 is about 550.0083646111.

The spelling of 166382591 in words is "one hundred sixty-six million, three hundred eighty-two thousand, five hundred ninety-one".