11918861 has 2 divisors, whose sum is σ = 11918862. Its totient is φ = 11918860.

The previous prime is 11918839. The next prime is 11918867. The reversal of 11918861 is 16881911.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10432900 + 1485961 = 3230^2 + 1219^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11918861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11918867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5959430 + 5959431.

It is an arithmetic number, because the mean of its divisors is an integer number (5959431).

Almost surely, 2^11918861 is an apocalyptic number.

It is an amenable number.

11918861 is a deficient number, since it is larger than the sum of its proper divisors (1).

11918861 is an equidigital number, since it uses as much as digits as its factorization.

11918861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 35.

The square root of 11918861 is about 3452.3703451397. The cubic root of 11918861 is about 228.4256757347.

The spelling of 11918861 in words is "eleven million, nine hundred eighteen thousand, eight hundred sixty-one".