11988639 has 24 divisors (see below), whose sum is σ = 19634160. Its totient is φ = 6988032.

The previous prime is 11988637. The next prime is 11988643. The reversal of 11988639 is 93688911.

11988639 is a `hidden beast` number, since 1 + 1 + 9 + 8 + 8 + 639 = 666.

It is not a de Polignac number, because 11988639 - 2¹ = 11988637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11988594 and 11988603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11988631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 474 + ... + 4919.

It is an arithmetic number, because the mean of its divisors is an integer number (818090).

Almost surely, 2^11988639 is an apocalyptic number.

11988639 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

11988639 is a deficient number, since it is larger than the sum of its proper divisors (7645521).

11988639 is a wasteful number, since it uses less digits than its factorization.

11988639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5431 (or 5428 counting only the distinct ones).

The product of its digits is 93312, while the sum is 45.

The square root of 11988639 is about 3462.4614077272. The cubic root of 11988639 is about 228.8705751503.

The spelling of 11988639 in words is "eleven million, nine hundred eighty-eight thousand, six hundred thirty-nine".