11311999 has 2 divisors, whose sum is σ = 11312000. Its totient is φ = 11311998.

The previous prime is 11311997. The next prime is 11312009. The reversal of 11311999 is 99911311.

11311999 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11311999 - 2¹ = 11311997 is a prime.

It is a super-2 number, since 2×11311999² = 255922642752002, which contains 22 as substring.

Together with 11311997, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11311997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5655999 + 5656000.

It is an arithmetic number, because the mean of its divisors is an integer number (5656000).

Almost surely, 2^11311999 is an apocalyptic number.

11311999 is a deficient number, since it is larger than the sum of its proper divisors (1).

11311999 is an equidigital number, since it uses as much as digits as its factorization.

11311999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2187, while the sum is 34.

The square root of 11311999 is about 3363.3315328703. The cubic root of 11311999 is about 224.4811021736.

The spelling of 11311999 in words is "eleven million, three hundred eleven thousand, nine hundred ninety-nine".