11981667 has 4 divisors (see below), whose sum is σ = 15975560. Its totient is φ = 7987776.

The previous prime is 11981659. The next prime is 11981701. The reversal of 11981667 is 76618911.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 11981667 - 2³ = 11981659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11981867) 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, 1996942 + ... + 1996947.

It is an arithmetic number, because the mean of its divisors is an integer number (3993890).

Almost surely, 2^11981667 is an apocalyptic number.

11981667 is a deficient number, since it is larger than the sum of its proper divisors (3993893).

11981667 is an equidigital number, since it uses as much as digits as its factorization.

11981667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3993892.

The product of its digits is 18144, while the sum is 39.

The square root of 11981667 is about 3461.4544630834. The cubic root of 11981667 is about 228.8261999416.

The spelling of 11981667 in words is "eleven million, nine hundred eighty-one thousand, six hundred sixty-seven".