11999999 has 4 divisors (see below), whose sum is σ = 13090920. Its totient is φ = 10909080.

The previous prime is 11999989. The next prime is 12000017. The reversal of 11999999 is 99999911.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99999911 = 11 ⋅9090901.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11999999 is a prime.

It is a Duffinian number.

11999999 is a modest number, since divided by 9999 gives 1199 as remainder.

It is a plaindrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11999929) 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 3 ways as a sum of consecutive naturals, for example, 545444 + ... + 545465.

It is an arithmetic number, because the mean of its divisors is an integer number (3272730).

Almost surely, 2^11999999 is an apocalyptic number.

11999999 is a deficient number, since it is larger than the sum of its proper divisors (1090921).

11999999 is a wasteful number, since it uses less digits than its factorization.

11999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1090920.

The product of its digits is 531441, while the sum is 56.

The square root of 11999999 is about 3464.1014708002. The cubic root of 11999999 is about 228.9428421511.

It can be divided in two parts, 119 and 99999, that multiplied together give a triangular number (11899881 = T₄₈₇₈).

The spelling of 11999999 in words is "eleven million, nine hundred ninety-nine thousand, nine hundred ninety-nine".