165251623 has 12 divisors (see below), whose sum is σ = 172554184. Its totient is φ = 158130000.

The previous prime is 165251617. The next prime is 165251641. The reversal of 165251623 is 326152561.

165251623 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 165251623 - 2¹⁷ = 165120551 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165251663) 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, 658248 + ... + 658498.

Almost surely, 2^165251623 is an apocalyptic number.

165251623 is a deficient number, since it is larger than the sum of its proper divisors (7302561).

165251623 is an frugal number, since it uses more digits than its factorization.

165251623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 606 (or 355 counting only the distinct ones).

The product of its digits is 10800, while the sum is 31.

The square root of 165251623 is about 12855.0232594111. The cubic root of 165251623 is about 548.7593224202.

The spelling of 165251623 in words is "one hundred sixty-five million, two hundred fifty-one thousand, six hundred twenty-three".