11721808 has 20 divisors (see below), whose sum is σ = 25955680. Its totient is φ = 5023584.

The previous prime is 11721799. The next prime is 11721811. The reversal of 11721808 is 80812711.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52218 + ... + 52441.

It is an arithmetic number, because the mean of its divisors is an integer number (1297784).

Almost surely, 2^11721808 is an apocalyptic number.

It is an amenable number.

11721808 is an abundant number, since it is smaller than the sum of its proper divisors (14233872).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11721808 is a wasteful number, since it uses less digits than its factorization.

11721808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104674 (or 104668 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 28.

The square root of 11721808 is about 3423.7126047611. The cubic root of 11721808 is about 227.1598297360.

The spelling of 11721808 in words is "eleven million, seven hundred twenty-one thousand, eight hundred eight".