66193871 has 4 divisors (see below), whose sum is σ = 66210144. Its totient is φ = 66177600.

The previous prime is 66193849. The next prime is 66193889. The reversal of 66193871 is 17839166.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 17839166 = 2 ⋅8919583.

It is a cyclic number.

It is not a de Polignac number, because 66193871 - 2⁶ = 66193807 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66198871) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4031 + ... + 12191.

It is an arithmetic number, because the mean of its divisors is an integer number (16552536).

Almost surely, 2^66193871 is an apocalyptic number.

66193871 is a deficient number, since it is larger than the sum of its proper divisors (16273).

66193871 is an equidigital number, since it uses as much as digits as its factorization.

66193871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16272.

The product of its digits is 54432, while the sum is 41.

The square root of 66193871 is about 8135.9615903715. The cubic root of 66193871 is about 404.5193118362.

The spelling of 66193871 in words is "sixty-six million, one hundred ninety-three thousand, eight hundred seventy-one".