66199843 has 2 divisors, whose sum is σ = 66199844. Its totient is φ = 66199842.

The previous prime is 66199841. The next prime is 66199877. The reversal of 66199843 is 34899166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66199843 - 2¹ = 66199841 is a prime.

Together with 66199841, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 66199793 and 66199802.

It is not a weakly prime, because it can be changed into another prime (66199841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33099921 + 33099922.

It is an arithmetic number, because the mean of its divisors is an integer number (33099922).

Almost surely, 2^66199843 is an apocalyptic number.

66199843 is a deficient number, since it is larger than the sum of its proper divisors (1).

66199843 is an equidigital number, since it uses as much as digits as its factorization.

66199843 is an evil number, because the sum of its binary digits is even.

The product of its digits is 279936, while the sum is 46.

The square root of 66199843 is about 8136.3285946427. The cubic root of 66199843 is about 404.5314766920.

The spelling of 66199843 in words is "sixty-six million, one hundred ninety-nine thousand, eight hundred forty-three".