11997647 has 2 divisors, whose sum is σ = 11997648. Its totient is φ = 11997646.

The previous prime is 11997637. The next prime is 11997649. The reversal of 11997647 is 74679911.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11997647 - 2²² = 7803343 is a prime.

Together with 11997649, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 11997598 and 11997607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11997649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5998823 + 5998824.

It is an arithmetic number, because the mean of its divisors is an integer number (5998824).

Almost surely, 2^11997647 is an apocalyptic number.

11997647 is a deficient number, since it is larger than the sum of its proper divisors (1).

11997647 is an equidigital number, since it uses as much as digits as its factorization.

11997647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 95256, while the sum is 44.

The square root of 11997647 is about 3463.7619721915. The cubic root of 11997647 is about 228.9278835735.

The spelling of 11997647 in words is "eleven million, nine hundred ninety-seven thousand, six hundred forty-seven".