165366661 has 2 divisors, whose sum is σ = 165366662. Its totient is φ = 165366660.

The previous prime is 165366637. The next prime is 165366673. The reversal of 165366661 is 166663561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 161036100 + 4330561 = 12690^2 + 2081^2 .

It is an emirp because it is prime and its reverse (166663561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165366661 - 2⁵ = 165366629 is a prime.

It is a super-2 number, since 2×165366661² = 54692265140577842, which contains 22 as substring.

It is equal to p_9258286 and since 165366661 and 9258286 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165366611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82683330 + 82683331.

It is an arithmetic number, because the mean of its divisors is an integer number (82683331).

Almost surely, 2^165366661 is an apocalyptic number.

It is an amenable number.

165366661 is a deficient number, since it is larger than the sum of its proper divisors (1).

165366661 is an equidigital number, since it uses as much as digits as its factorization.

165366661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116640, while the sum is 40.

The square root of 165366661 is about 12859.4969186201. The cubic root of 165366661 is about 548.8866303619.

The spelling of 165366661 in words is "one hundred sixty-five million, three hundred sixty-six thousand, six hundred sixty-one".