11187661 has 4 divisors (see below), whose sum is σ = 11202300. Its totient is φ = 11173024.

The previous prime is 11187643. The next prime is 11187667. The reversal of 11187661 is 16678111.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5851561 + 5336100 = 2419^2 + 2310^2 .

It is a cyclic number.

It is not a de Polignac number, because 11187661 - 2⁹ = 11187149 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 (11187667) 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, 6106 + ... + 7723.

It is an arithmetic number, because the mean of its divisors is an integer number (2800575).

Almost surely, 2^11187661 is an apocalyptic number.

It is an amenable number.

11187661 is a deficient number, since it is larger than the sum of its proper divisors (14639).

11187661 is an equidigital number, since it uses as much as digits as its factorization.

11187661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14638.

The product of its digits is 2016, while the sum is 31.

The square root of 11187661 is about 3344.7961073883. The cubic root of 11187661 is about 223.6555945172.

The spelling of 11187661 in words is "eleven million, one hundred eighty-seven thousand, six hundred sixty-one".