11987986 has 4 divisors (see below), whose sum is σ = 17981982. Its totient is φ = 5993992.

The previous prime is 11987981. The next prime is 11988029. The reversal of 11987986 is 68978911.

11987986 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 11771761 + 216225 = 3431^2 + 465^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (11987981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2996995 + ... + 2996998.

Almost surely, 2^11987986 is an apocalyptic number.

11987986 is a deficient number, since it is larger than the sum of its proper divisors (5993996).

11987986 is an equidigital number, since it uses as much as digits as its factorization.

11987986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5993995.

The product of its digits is 217728, while the sum is 49.

The square root of 11987986 is about 3462.3671093632. The cubic root of 11987986 is about 228.8664196828.

The spelling of 11987986 in words is "eleven million, nine hundred eighty-seven thousand, nine hundred eighty-six".