11156661 has 12 divisors (see below), whose sum is σ = 16156140. Its totient is φ = 7418880.

The previous prime is 11156657. The next prime is 11156669. The reversal of 11156661 is 16665111.

It can be written as a sum of positive squares in 2 ways, for example, as 1664100 + 9492561 = 1290^2 + 3081^2 .

It is not a de Polignac number, because 11156661 - 2² = 11156657 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11156669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2805 + ... + 5493.

It is an arithmetic number, because the mean of its divisors is an integer number (1346345).

Almost surely, 2^11156661 is an apocalyptic number.

It is an amenable number.

11156661 is a deficient number, since it is larger than the sum of its proper divisors (4999479).

11156661 is a wasteful number, since it uses less digits than its factorization.

11156661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3156 (or 3153 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 11156661 is about 3340.1588285589. The cubic root of 11156661 is about 223.4488269251.

It can be divided in two parts, 1115 and 6661, that added together give a 5-th power (7776 = 6⁵).

The spelling of 11156661 in words is "eleven million, one hundred fifty-six thousand, six hundred sixty-one".