11778721 has 8 divisors (see below), whose sum is σ = 11995200. Its totient is φ = 11564400.

The previous prime is 11778719. The next prime is 11778731. The reversal of 11778721 is 12787711.

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 11778721 - 2¹ = 11778719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11778731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13620 + ... + 14458.

It is an arithmetic number, because the mean of its divisors is an integer number (1499400).

Almost surely, 2^11778721 is an apocalyptic number.

It is an amenable number.

11778721 is a deficient number, since it is larger than the sum of its proper divisors (216479).

11778721 is a wasteful number, since it uses less digits than its factorization.

11778721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1079.

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

The square root of 11778721 is about 3432.0141316725. The cubic root of 11778721 is about 227.5268800506.

The spelling of 11778721 in words is "eleven million, seven hundred seventy-eight thousand, seven hundred twenty-one".