11667981 has 8 divisors (see below), whose sum is σ = 16754080. Its totient is φ = 7180272.

The previous prime is 11667977. The next prime is 11667991. The reversal of 11667981 is 18976611.

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

It is not a de Polignac number, because 11667981 - 2² = 11667977 is a prime.

It is a super-2 number, since 2×11667981² = 272283561232722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 299179 = 11667981 / (1 + 1 + 6 + 6 + 7 + 9 + 8 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11667911) 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, 149551 + ... + 149628.

It is an arithmetic number, because the mean of its divisors is an integer number (2094260).

Almost surely, 2^11667981 is an apocalyptic number.

It is an amenable number.

11667981 is a deficient number, since it is larger than the sum of its proper divisors (5086099).

11667981 is a wasteful number, since it uses less digits than its factorization.

11667981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 299195.

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

The square root of 11667981 is about 3415.8426486008. The cubic root of 11667981 is about 226.8115872073.

The spelling of 11667981 in words is "eleven million, six hundred sixty-seven thousand, nine hundred eighty-one".