11976981 has 4 divisors (see below), whose sum is σ = 15969312. Its totient is φ = 7984652.

The previous prime is 11976949. The next prime is 11977003. The reversal of 11976981 is 18967911.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18967911 = 3 ⋅6322637.

It is a cyclic number.

It is not a de Polignac number, because 11976981 - 2⁵ = 11976949 is a prime.

It is a super-2 number, since 2×11976981² = 286896147748722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11976901) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 1996161 + ... + 1996166.

It is an arithmetic number, because the mean of its divisors is an integer number (3992328).

Almost surely, 2^11976981 is an apocalyptic number.

It is an amenable number.

11976981 is a deficient number, since it is larger than the sum of its proper divisors (3992331).

11976981 is an equidigital number, since it uses as much as digits as its factorization.

11976981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3992330.

The product of its digits is 27216, while the sum is 42.

The square root of 11976981 is about 3460.7775137966. Note that the first 3 decimals coincide. The cubic root of 11976981 is about 228.7963649336.

The spelling of 11976981 in words is "eleven million, nine hundred seventy-six thousand, nine hundred eighty-one".