11721897 has 24 divisors (see below), whose sum is σ = 18607680. Its totient is φ = 7051680.

The previous prime is 11721893. The next prime is 11721911. The reversal of 11721897 is 79812711.

It is not a de Polignac number, because 11721897 - 2² = 11721893 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11721893) 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 23 ways as a sum of consecutive naturals, for example, 16179 + ... + 16887.

It is an arithmetic number, because the mean of its divisors is an integer number (775320).

Almost surely, 2^11721897 is an apocalyptic number.

It is an amenable number.

11721897 is a deficient number, since it is larger than the sum of its proper divisors (6885783).

11721897 is a wasteful number, since it uses less digits than its factorization.

11721897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 893 (or 890 counting only the distinct ones).

The product of its digits is 7056, while the sum is 36.

The square root of 11721897 is about 3423.7256023227. The cubic root of 11721897 is about 227.1604046523.

The spelling of 11721897 in words is "eleven million, seven hundred twenty-one thousand, eight hundred ninety-seven".