165912553 has 2 divisors, whose sum is σ = 165912554. Its totient is φ = 165912552.

The previous prime is 165912511. The next prime is 165912557. The reversal of 165912553 is 355219561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 118962649 + 46949904 = 10907^2 + 6852^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165912553 is a prime.

It is not a weakly prime, because it can be changed into another prime (165912557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82956276 + 82956277.

It is an arithmetic number, because the mean of its divisors is an integer number (82956277).

Almost surely, 2^165912553 is an apocalyptic number.

It is an amenable number.

165912553 is a deficient number, since it is larger than the sum of its proper divisors (1).

165912553 is an equidigital number, since it uses as much as digits as its factorization.

165912553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40500, while the sum is 37.

The square root of 165912553 is about 12880.7046779281. The cubic root of 165912553 is about 549.4899436616.

The spelling of 165912553 in words is "one hundred sixty-five million, nine hundred twelve thousand, five hundred fifty-three".