66233991 has 8 divisors (see below), whose sum is σ = 88358400. Its totient is φ = 44132792.

The previous prime is 66233977. The next prime is 66234001. The reversal of 66233991 is 19933266.

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 66233991 - 2¹⁹ = 65709703 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66233911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2596 + ... + 11798.

It is an arithmetic number, because the mean of its divisors is an integer number (11044800).

Almost surely, 2^66233991 is an apocalyptic number.

66233991 is a deficient number, since it is larger than the sum of its proper divisors (22124409).

66233991 is a wasteful number, since it uses less digits than its factorization.

66233991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11605.

The product of its digits is 52488, while the sum is 39.

The square root of 66233991 is about 8138.4268135801. The cubic root of 66233991 is about 404.6010215011.

The spelling of 66233991 in words is "sixty-six million, two hundred thirty-three thousand, nine hundred ninety-one".