11991457 has 2 divisors, whose sum is σ = 11991458. Its totient is φ = 11991456.

The previous prime is 11991449. The next prime is 11991461. The reversal of 11991457 is 75419911.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11861136 + 130321 = 3444^2 + 361^2 .

It is a cyclic number.

It is not a de Polignac number, because 11991457 - 2³ = 11991449 is a prime.

It is not a weakly prime, because it can be changed into another prime (11991407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5995728 + 5995729.

It is an arithmetic number, because the mean of its divisors is an integer number (5995729).

Almost surely, 2^11991457 is an apocalyptic number.

It is an amenable number.

11991457 is a deficient number, since it is larger than the sum of its proper divisors (1).

11991457 is an equidigital number, since it uses as much as digits as its factorization.

11991457 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11340, while the sum is 37.

The square root of 11991457 is about 3462.8683197604. The cubic root of 11991457 is about 228.8885062030. Note that the first 3 decimals are identical.

The spelling of 11991457 in words is "eleven million, nine hundred ninety-one thousand, four hundred fifty-seven".