16978265 has 4 divisors (see below), whose sum is σ = 20373924. Its totient is φ = 13582608.

The previous prime is 16978259. The next prime is 16978271. The reversal of 16978265 is 56287961.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (16978259) and next prime (16978271).

It can be written as a sum of positive squares in 2 ways, for example, as 8340544 + 8637721 = 2888^2 + 2939^2 .

It is a cyclic number.

It is not a de Polignac number, because 16978265 - 2⁸ = 16978009 is a prime.

It is a super-2 number, since 2×16978265² = 576522964820450, which contains 22 as substring.

It is a Duffinian number.

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, 1697822 + ... + 1697831.

It is an arithmetic number, because the mean of its divisors is an integer number (5093481).

Almost surely, 2^16978265 is an apocalyptic number.

It is an amenable number.

16978265 is a deficient number, since it is larger than the sum of its proper divisors (3395659).

16978265 is an equidigital number, since it uses as much as digits as its factorization.

16978265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3395658.

The product of its digits is 181440, while the sum is 44.

The square root of 16978265 is about 4120.4690267007. The cubic root of 16978265 is about 257.0185303600.

The spelling of 16978265 in words is "sixteen million, nine hundred seventy-eight thousand, two hundred sixty-five".