18331965 has 12 divisors (see below), whose sum is σ = 31775484. Its totient is φ = 9777024.

The previous prime is 18331939. The next prime is 18331969. The reversal of 18331965 is 56913381.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 12236004 + 6095961 = 3498^2 + 2469^2 .

It is not a de Polignac number, because 18331965 - 2¹⁰ = 18330941 is a prime.

It is a super-2 number, since 2×18331965² = 672121881522450, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18331969) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 203644 + ... + 203733.

It is an arithmetic number, because the mean of its divisors is an integer number (2647957).

Almost surely, 2^18331965 is an apocalyptic number.

18331965 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18331965 is a deficient number, since it is larger than the sum of its proper divisors (13443519).

18331965 is a wasteful number, since it uses less digits than its factorization.

18331965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407388 (or 407385 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 18331965 is about 4281.5844029985. The cubic root of 18331965 is about 263.6754361972.

The spelling of 18331965 in words is "eighteen million, three hundred thirty-one thousand, nine hundred sixty-five".