11571999 has 16 divisors (see below), whose sum is σ = 15774720. Its totient is φ = 7544160.

The previous prime is 11571983. The next prime is 11572037. The reversal of 11571999 is 99917511.

It is a happy number.

11571999 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11571999 - 2⁴ = 11571983 is a prime.

It is a super-2 number, since 2×11571999² = 267822321712002, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 11571999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11571929) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37054 + ... + 37364.

It is an arithmetic number, because the mean of its divisors is an integer number (985920).

Almost surely, 2^11571999 is an apocalyptic number.

11571999 is a deficient number, since it is larger than the sum of its proper divisors (4202721).

11571999 is a wasteful number, since it uses less digits than its factorization.

11571999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 550.

The product of its digits is 25515, while the sum is 42.

The square root of 11571999 is about 3401.7641011687. The cubic root of 11571999 is about 226.1879489593.

The spelling of 11571999 in words is "eleven million, five hundred seventy-one thousand, nine hundred ninety-nine".