66233891 has 2 divisors, whose sum is σ = 66233892. Its totient is φ = 66233890.

The previous prime is 66233851. The next prime is 66233903. The reversal of 66233891 is 19833266.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66233891 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66233821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33116945 + 33116946.

It is an arithmetic number, because the mean of its divisors is an integer number (33116946).

Almost surely, 2^66233891 is an apocalyptic number.

66233891 is a deficient number, since it is larger than the sum of its proper divisors (1).

66233891 is an equidigital number, since it uses as much as digits as its factorization.

66233891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46656, while the sum is 38.

The square root of 66233891 is about 8138.4206698843. The cubic root of 66233891 is about 404.6008178789.

The spelling of 66233891 in words is "sixty-six million, two hundred thirty-three thousand, eight hundred ninety-one".