11997718 has 4 divisors (see below), whose sum is σ = 17996580. Its totient is φ = 5998858.

The previous prime is 11997691. The next prime is 11997751. The reversal of 11997718 is 81779911.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81779911 = 17 ⋅4810583.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2999428 + ... + 2999431.

It is an arithmetic number, because the mean of its divisors is an integer number (4499145).

Almost surely, 2^11997718 is an apocalyptic number.

11997718 is a deficient number, since it is larger than the sum of its proper divisors (5998862).

11997718 is an equidigital number, since it uses as much as digits as its factorization.

11997718 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5998861.

The product of its digits is 31752, while the sum is 43.

The square root of 11997718 is about 3463.7722211485. The cubic root of 11997718 is about 228.9283351579.

The spelling of 11997718 in words is "eleven million, nine hundred ninety-seven thousand, seven hundred eighteen".