11987505 has 24 divisors (see below), whose sum is σ = 20859072. Its totient is φ = 6368544.

The previous prime is 11987501. The next prime is 11987579. The reversal of 11987505 is 50578911.

It is not a de Polignac number, because 11987505 - 2² = 11987501 is a prime.

It is a super-3 number, since 3×11987505³ (a number of 22 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 11987505.

It is not an unprimeable number, because it can be changed into a prime (11987501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21642 + ... + 22188.

It is an arithmetic number, because the mean of its divisors is an integer number (869128).

Almost surely, 2^11987505 is an apocalyptic number.

11987505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

11987505 is a deficient number, since it is larger than the sum of its proper divisors (8871567).

11987505 is a wasteful number, since it uses less digits than its factorization.

11987505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1045 (or 1042 counting only the distinct ones).

The product of its (nonzero) digits is 12600, while the sum is 36.

The square root of 11987505 is about 3462.2976475167. The cubic root of 11987505 is about 228.8633586677.

The spelling of 11987505 in words is "eleven million, nine hundred eighty-seven thousand, five hundred five".