11775661 has 4 divisors (see below), whose sum is σ = 11924800. Its totient is φ = 11626524.

The previous prime is 11775641. The next prime is 11775677. The reversal of 11775661 is 16657711.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16657711 = 7 ⋅2379673.

It is a cyclic number.

It is not a de Polignac number, because 11775661 - 2¹¹ = 11773613 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 (11775601) 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, 74451 + ... + 74608.

It is an arithmetic number, because the mean of its divisors is an integer number (2981200).

Almost surely, 2^11775661 is an apocalyptic number.

It is an amenable number.

11775661 is a deficient number, since it is larger than the sum of its proper divisors (149139).

11775661 is an equidigital number, since it uses as much as digits as its factorization.

11775661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149138.

The product of its digits is 8820, while the sum is 34.

The square root of 11775661 is about 3431.5683003548. The cubic root of 11775661 is about 227.5071752356.

The spelling of 11775661 in words is "eleven million, seven hundred seventy-five thousand, six hundred sixty-one".