11691919 has 4 divisors (see below), whose sum is σ = 11699640. Its totient is φ = 11684200.

The previous prime is 11691917. The next prime is 11691923. The reversal of 11691919 is 91919611.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 91919611 = 7 ⋅13131373.

It is a cyclic number.

It is not a de Polignac number, because 11691919 - 2¹ = 11691917 is a prime.

It is a super-2 number, since 2×11691919² = 273401939805122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11691917) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 757 + ... + 4894.

It is an arithmetic number, because the mean of its divisors is an integer number (2924910).

Almost surely, 2^11691919 is an apocalyptic number.

11691919 is a deficient number, since it is larger than the sum of its proper divisors (7721).

11691919 is an equidigital number, since it uses as much as digits as its factorization.

11691919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7720.

The product of its digits is 4374, while the sum is 37.

The square root of 11691919 is about 3419.3448202836. The cubic root of 11691919 is about 226.9665899454.

The spelling of 11691919 in words is "eleven million, six hundred ninety-one thousand, nine hundred nineteen".