11997919 has 2 divisors, whose sum is σ = 11997920. Its totient is φ = 11997918.

The previous prime is 11997917. The next prime is 11997929. The reversal of 11997919 is 91979911.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 11997919 - 2¹ = 11997917 is a prime.

It is a super-2 number, since 2×11997919² = 287900120661122, which contains 22 as substring.

Together with 11997917, 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 (11997913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5998959 + 5998960.

It is an arithmetic number, because the mean of its divisors is an integer number (5998960).

Almost surely, 2^11997919 is an apocalyptic number.

11997919 is a deficient number, since it is larger than the sum of its proper divisors (1).

11997919 is an equidigital number, since it uses as much as digits as its factorization.

11997919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45927, while the sum is 46.

The square root of 11997919 is about 3463.8012356369. The cubic root of 11997919 is about 228.9296135770.

The spelling of 11997919 in words is "eleven million, nine hundred ninety-seven thousand, nine hundred nineteen".