11699991 has 16 divisors (see below), whose sum is σ = 18246400. Its totient is φ = 7389144.

The previous prime is 11699971. The next prime is 11699993. The reversal of 11699991 is 19999611.

11699991 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11699991 - 2⁵ = 11699959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11699993) 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, 10891 + ... + 11916.

It is an arithmetic number, because the mean of its divisors is an integer number (1140400).

Almost surely, 2^11699991 is an apocalyptic number.

11699991 is a deficient number, since it is larger than the sum of its proper divisors (6546409).

11699991 is a wasteful number, since it uses less digits than its factorization.

11699991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22835 (or 22829 counting only the distinct ones).

The product of its digits is 39366, while the sum is 45.

The square root of 11699991 is about 3420.5249597101. The cubic root of 11699991 is about 227.0188098550.

The spelling of 11699991 in words is "eleven million, six hundred ninety-nine thousand, nine hundred ninety-one".