165917799 has 12 divisors (see below), whose sum is σ = 239904912. Its totient is φ = 110498400.

The previous prime is 165917761. The next prime is 165917809. The reversal of 165917799 is 997719561.

It is a happy number.

It is not a de Polignac number, because 165917799 - 2¹² = 165913703 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165917099) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 339 + ... + 18219.

It is an arithmetic number, because the mean of its divisors is an integer number (19992076).

Almost surely, 2^165917799 is an apocalyptic number.

165917799 is a deficient number, since it is larger than the sum of its proper divisors (73987113).

165917799 is a wasteful number, since it uses less digits than its factorization.

165917799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18918 (or 18915 counting only the distinct ones).

The product of its digits is 1071630, while the sum is 54.

The square root of 165917799 is about 12880.9083142455. The cubic root of 165917799 is about 549.4957350535.

The spelling of 165917799 in words is "one hundred sixty-five million, nine hundred seventeen thousand, seven hundred ninety-nine".