165218847225 has 24 divisors (see below), whose sum is σ = 273176072160. Its totient is φ = 88112123520.

The previous prime is 165218847217. The next prime is 165218847259. The reversal of 165218847225 is 522748812561.

It is a happy number.

It is not a de Polignac number, because 165218847225 - 2³ = 165218847217 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1779402 + ... + 1869948.

It is an arithmetic number, because the mean of its divisors is an integer number (11382336340).

Almost surely, 2^165218847225 is an apocalyptic number.

165218847225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

165218847225 is a deficient number, since it is larger than the sum of its proper divisors (107957224935).

165218847225 is a wasteful number, since it uses less digits than its factorization.

165218847225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114889 (or 114884 counting only the distinct ones).

The product of its digits is 2150400, while the sum is 51.

The spelling of 165218847225 in words is "one hundred sixty-five billion, two hundred eighteen million, eight hundred forty-seven thousand, two hundred twenty-five".