11778817 has 4 divisors (see below), whose sum is σ = 11786580. Its totient is φ = 11771056.

The previous prime is 11778797. The next prime is 11778847. The reversal of 11778817 is 71887711.

11778817 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It can be written as a sum of positive squares in 2 ways, for example, as 1640961 + 10137856 = 1281^2 + 3184^2 .

It is a cyclic number.

It is not a de Polignac number, because 11778817 - 2²³ = 3390209 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11778817.

It is not an unprimeable number, because it can be changed into a prime (11778847) 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, 778 + ... + 4915.

It is an arithmetic number, because the mean of its divisors is an integer number (2946645).

Almost surely, 2^11778817 is an apocalyptic number.

It is an amenable number.

11778817 is a deficient number, since it is larger than the sum of its proper divisors (7763).

11778817 is an equidigital number, since it uses as much as digits as its factorization.

11778817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7762.

The product of its digits is 21952, while the sum is 40.

The square root of 11778817 is about 3432.0281176004. The cubic root of 11778817 is about 227.5274981856.

The spelling of 11778817 in words is "eleven million, seven hundred seventy-eight thousand, eight hundred seventeen".