165215251 has 2 divisors, whose sum is σ = 165215252. Its totient is φ = 165215250.

The previous prime is 165215221. The next prime is 165215273. The reversal of 165215251 is 152512561.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 165215251 - 2¹⁵ = 165182483 is a prime.

It is not a weakly prime, because it can be changed into another prime (165215201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82607625 + 82607626.

It is an arithmetic number, because the mean of its divisors is an integer number (82607626).

Almost surely, 2^165215251 is an apocalyptic number.

165215251 is a deficient number, since it is larger than the sum of its proper divisors (1).

165215251 is an equidigital number, since it uses as much as digits as its factorization.

165215251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3000, while the sum is 28.

The square root of 165215251 is about 12853.6084816677. The cubic root of 165215251 is about 548.7190586934.

The spelling of 165215251 in words is "one hundred sixty-five million, two hundred fifteen thousand, two hundred fifty-one".