11931987 has 8 divisors (see below), whose sum is σ = 15943936. Its totient is φ = 7937352.

The previous prime is 11931967. The next prime is 11931989. The reversal of 11931987 is 78913911.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 11931987 - 2¹² = 11927891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11931989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2623 + ... + 5544.

It is an arithmetic number, because the mean of its divisors is an integer number (1992992).

Almost surely, 2^11931987 is an apocalyptic number.

11931987 is a deficient number, since it is larger than the sum of its proper divisors (4011949).

11931987 is an equidigital number, since it uses as much as digits as its factorization.

11931987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8657.

The product of its digits is 13608, while the sum is 39.

The square root of 11931987 is about 3454.2708347783. The cubic root of 11931987 is about 228.5094984935.

The spelling of 11931987 in words is "eleven million, nine hundred thirty-one thousand, nine hundred eighty-seven".