66420199 has 4 divisors (see below), whose sum is σ = 66480160. Its totient is φ = 66360240.

The previous prime is 66420187. The next prime is 66420223. The reversal of 66420199 is 99102466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99102466 = 2 ⋅49551233.

It is a cyclic number.

It is not a de Polignac number, because 66420199 - 2¹⁹ = 65895911 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 (66420149) 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, 28287 + ... + 30544.

It is an arithmetic number, because the mean of its divisors is an integer number (16620040).

Almost surely, 2^66420199 is an apocalyptic number.

66420199 is a deficient number, since it is larger than the sum of its proper divisors (59961).

66420199 is a wasteful number, since it uses less digits than its factorization.

66420199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59960.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 66420199 is about 8149.8588331332. The cubic root of 66420199 is about 404.9798272734.

The spelling of 66420199 in words is "sixty-six million, four hundred twenty thousand, one hundred ninety-nine".