165231555 has 32 divisors (see below), whose sum is σ = 273881088. Its totient is φ = 85008000.

The previous prime is 165231553. The next prime is 165231569. The reversal of 165231555 is 555132561.

It is not a de Polignac number, because 165231555 - 2¹ = 165231553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (165231553) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 48405 + ... + 51705.

It is an arithmetic number, because the mean of its divisors is an integer number (8558784).

Almost surely, 2^165231555 is an apocalyptic number.

165231555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

165231555 is a deficient number, since it is larger than the sum of its proper divisors (108649533).

165231555 is a wasteful number, since it uses less digits than its factorization.

165231555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3427.

The product of its digits is 22500, while the sum is 33.

The square root of 165231555 is about 12854.2426848103. The cubic root of 165231555 is about 548.7371079175.

The spelling of 165231555 in words is "one hundred sixty-five million, two hundred thirty-one thousand, five hundred fifty-five".