165266551 has 2 divisors, whose sum is σ = 165266552. Its totient is φ = 165266550.

The previous prime is 165266539. The next prime is 165266593. The reversal of 165266551 is 155662561.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165266551 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 165266551.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165266051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82633275 + 82633276.

It is an arithmetic number, because the mean of its divisors is an integer number (82633276).

Almost surely, 2^165266551 is an apocalyptic number.

165266551 is a deficient number, since it is larger than the sum of its proper divisors (1).

165266551 is an equidigital number, since it uses as much as digits as its factorization.

165266551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54000, while the sum is 37.

The square root of 165266551 is about 12855.6038753533. The cubic root of 165266551 is about 548.7758459745.

The spelling of 165266551 in words is "one hundred sixty-five million, two hundred sixty-six thousand, five hundred fifty-one".