18816945 has 16 divisors (see below), whose sum is σ = 34408320. Its totient is φ = 8601984.

The previous prime is 18816923. The next prime is 18816983. The reversal of 18816945 is 54961881.

It is not a de Polignac number, because 18816945 - 2⁸ = 18816689 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 18816897 and 18816906.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 89500 + ... + 89709.

It is an arithmetic number, because the mean of its divisors is an integer number (2150520).

Almost surely, 2^18816945 is an apocalyptic number.

18816945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18816945 is a deficient number, since it is larger than the sum of its proper divisors (15591375).

18816945 is a wasteful number, since it uses less digits than its factorization.

18816945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179224.

The product of its digits is 69120, while the sum is 42.

The square root of 18816945 is about 4337.8502740413. The cubic root of 18816945 is about 265.9804430946.

The spelling of 18816945 in words is "eighteen million, eight hundred sixteen thousand, nine hundred forty-five".