11997831 has 8 divisors (see below), whose sum is σ = 16337664. Its totient is φ = 7828280.

The previous prime is 11997829. The next prime is 11997841. The reversal of 11997831 is 13879911.

11997831 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11997831 - 2¹ = 11997829 is a prime.

It is a super-2 number, since 2×11997831² = 287895897409122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 11997831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11997841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42405 + ... + 42686.

It is an arithmetic number, because the mean of its divisors is an integer number (2042208).

Almost surely, 2^11997831 is an apocalyptic number.

11997831 is a deficient number, since it is larger than the sum of its proper divisors (4339833).

11997831 is an equidigital number, since it uses as much as digits as its factorization.

11997831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85141.

The product of its digits is 13608, while the sum is 39.

The square root of 11997831 is about 3463.7885328062. The cubic root of 11997831 is about 228.9290538729.

The spelling of 11997831 in words is "eleven million, nine hundred ninety-seven thousand, eight hundred thirty-one".