11997287 has 4 divisors (see below), whose sum is σ = 12321576. Its totient is φ = 11673000.

The previous prime is 11997277. The next prime is 11997299. The reversal of 11997287 is 78279911.

11997287 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78279911 = 3323 ⋅23557.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11997287 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 (11997247) 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, 162089 + ... + 162162.

It is an arithmetic number, because the mean of its divisors is an integer number (3080394).

Almost surely, 2^11997287 is an apocalyptic number.

11997287 is a deficient number, since it is larger than the sum of its proper divisors (324289).

11997287 is an equidigital number, since it uses as much as digits as its factorization.

11997287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324288.

The product of its digits is 63504, while the sum is 44.

The square root of 11997287 is about 3463.7100051823. The cubic root of 11997287 is about 228.9255938228.

The spelling of 11997287 in words is "eleven million, nine hundred ninety-seven thousand, two hundred eighty-seven".