11987511 has 4 divisors (see below), whose sum is σ = 15983352. Its totient is φ = 7991672.

The previous prime is 11987501. The next prime is 11987579. The reversal of 11987511 is 11578911.

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

It is a cyclic number.

It is not a de Polignac number, because 11987511 - 2⁹ = 11986999 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11987501) 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, 1997916 + ... + 1997921.

It is an arithmetic number, because the mean of its divisors is an integer number (3995838).

Almost surely, 2^11987511 is an apocalyptic number.

11987511 is a deficient number, since it is larger than the sum of its proper divisors (3995841).

11987511 is an equidigital number, since it uses as much as digits as its factorization.

11987511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3995840.

The product of its digits is 2520, while the sum is 33.

The square root of 11987511 is about 3462.2985139933. The cubic root of 11987511 is about 228.8633968513.

The spelling of 11987511 in words is "eleven million, nine hundred eighty-seven thousand, five hundred eleven".