11987566 has 4 divisors (see below), whose sum is σ = 17981352. Its totient is φ = 5993782.

The previous prime is 11987501. The next prime is 11987579. The reversal of 11987566 is 66578911.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66578911 = 7 ⋅9511273.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2996890 + ... + 2996893.

It is an arithmetic number, because the mean of its divisors is an integer number (4495338).

Almost surely, 2^11987566 is an apocalyptic number.

11987566 is a deficient number, since it is larger than the sum of its proper divisors (5993786).

11987566 is an equidigital number, since it uses as much as digits as its factorization.

11987566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5993785.

The product of its digits is 90720, while the sum is 43.

The square root of 11987566 is about 3462.3064566846. The cubic root of 11987566 is about 228.8637468675.

The spelling of 11987566 in words is "eleven million, nine hundred eighty-seven thousand, five hundred sixty-six".