11999965 has 4 divisors (see below), whose sum is σ = 14399964. Its totient is φ = 9599968.

The previous prime is 11999941. The next prime is 11999987. The reversal of 11999965 is 56999911.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56999911 = 23 ⋅2478257.

It can be written as a sum of positive squares in 2 ways, for example, as 6340324 + 5659641 = 2518^2 + 2379^2 .

It is a cyclic number.

It is not a de Polignac number, because 11999965 - 2⁷ = 11999837 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent 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, 1199992 + ... + 1200001.

It is an arithmetic number, because the mean of its divisors is an integer number (3599991).

Almost surely, 2^11999965 is an apocalyptic number.

It is an amenable number.

11999965 is a deficient number, since it is larger than the sum of its proper divisors (2399999).

11999965 is an equidigital number, since it uses as much as digits as its factorization.

11999965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2399998.

The product of its digits is 196830, while the sum is 49.

The square root of 11999965 is about 3464.0965633192. The cubic root of 11999965 is about 228.9426259271.

The spelling of 11999965 in words is "eleven million, nine hundred ninety-nine thousand, nine hundred sixty-five".