16172665 has 4 divisors (see below), whose sum is σ = 19407204. Its totient is φ = 12938128.

The previous prime is 16172647. The next prime is 16172693. The reversal of 16172665 is 56627161.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56627161 = 53 ⋅1068437.

It can be written as a sum of positive squares in 2 ways, for example, as 8714304 + 7458361 = 2952^2 + 2731^2 .

It is a cyclic number.

It is not a de Polignac number, because 16172665 - 2⁷ = 16172537 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 16172665.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1617262 + ... + 1617271.

It is an arithmetic number, because the mean of its divisors is an integer number (4851801).

Almost surely, 2^16172665 is an apocalyptic number.

It is an amenable number.

16172665 is a deficient number, since it is larger than the sum of its proper divisors (3234539).

16172665 is an equidigital number, since it uses as much as digits as its factorization.

16172665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3234538.

The product of its digits is 15120, while the sum is 34.

The square root of 16172665 is about 4021.5252081766. The cubic root of 16172665 is about 252.8874032235.

The spelling of 16172665 in words is "sixteen million, one hundred seventy-two thousand, six hundred sixty-five".