11787721 has 8 divisors (see below), whose sum is σ = 12888000. Its totient is φ = 10692240.

The previous prime is 11787691. The next prime is 11787739. The reversal of 11787721 is 12778711.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11787721 - 2⁵ = 11787689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11787751) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5695 + ... + 7483.

It is an arithmetic number, because the mean of its divisors is an integer number (1611000).

Almost surely, 2^11787721 is an apocalyptic number.

11787721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11787721 is a deficient number, since it is larger than the sum of its proper divisors (1100279).

11787721 is a wasteful number, since it uses less digits than its factorization.

11787721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2399.

The product of its digits is 5488, while the sum is 34.

The square root of 11787721 is about 3433.3250647150. The cubic root of 11787721 is about 227.5848156161.

The spelling of 11787721 in words is "eleven million, seven hundred eighty-seven thousand, seven hundred twenty-one".