11847721 has 2 divisors, whose sum is σ = 11847722. Its totient is φ = 11847720.

The previous prime is 11847701. The next prime is 11847749. The reversal of 11847721 is 12774811.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11696400 + 151321 = 3420^2 + 389^2 .

It is a cyclic number.

It is not a de Polignac number, because 11847721 - 2⁷ = 11847593 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (11847701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5923860 + 5923861.

It is an arithmetic number, because the mean of its divisors is an integer number (5923861).

Almost surely, 2^11847721 is an apocalyptic number.

It is an amenable number.

11847721 is a deficient number, since it is larger than the sum of its proper divisors (1).

11847721 is an equidigital number, since it uses as much as digits as its factorization.

11847721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3136, while the sum is 31.

The square root of 11847721 is about 3442.0518589934. The cubic root of 11847721 is about 227.9703010973.

The spelling of 11847721 in words is "eleven million, eight hundred forty-seven thousand, seven hundred twenty-one".