11965999 has 4 divisors (see below), whose sum is σ = 12144664. Its totient is φ = 11787336.

The previous prime is 11965979. The next prime is 11966023. The reversal of 11965999 is 99956911.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99956911 = 509 ⋅196379.

It is a cyclic number.

It is not a de Polignac number, because 11965999 - 2¹⁹ = 11441711 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11965949) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 89232 + ... + 89365.

It is an arithmetic number, because the mean of its divisors is an integer number (3036166).

Almost surely, 2^11965999 is an apocalyptic number.

11965999 is a deficient number, since it is larger than the sum of its proper divisors (178665).

11965999 is an equidigital number, since it uses as much as digits as its factorization.

11965999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178664.

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

The square root of 11965999 is about 3459.1905122442. The cubic root of 11965999 is about 228.7264138043.

The spelling of 11965999 in words is "eleven million, nine hundred sixty-five thousand, nine hundred ninety-nine".