11979111 has 4 divisors (see below), whose sum is σ = 15972152. Its totient is φ = 7986072.

The previous prime is 11979109. The next prime is 11979127. The reversal of 11979111 is 11197911.

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

It is not a de Polignac number, because 11979111 - 2¹ = 11979109 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 (11979151) 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, 1996516 + ... + 1996521.

It is an arithmetic number, because the mean of its divisors is an integer number (3993038).

Almost surely, 2^11979111 is an apocalyptic number.

11979111 is a deficient number, since it is larger than the sum of its proper divisors (3993041).

11979111 is an equidigital number, since it uses as much as digits as its factorization.

11979111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3993040.

The product of its digits is 567, while the sum is 30.

The square root of 11979111 is about 3461.0852344315. The cubic root of 11979111 is about 228.8099272654.

It can be divided in two parts, 11979 and 111, that added together give a triangular number (12090 = T₁₅₅).

The spelling of 11979111 in words is "eleven million, nine hundred seventy-nine thousand, one hundred eleven".