66398319 has 16 divisors (see below), whose sum is σ = 105935200. Its totient is φ = 40860288.

The previous prime is 66398281. The next prime is 66398323. The reversal of 66398319 is 91389366.

66398319 is a `hidden beast` number, since 6 + 639 + 8 + 3 + 1 + 9 = 666.

It is not a de Polignac number, because 66398319 - 2⁷ = 66398191 is a prime.

It is a super-2 number, since 2×66398319² = 8817473532051522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66398329) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94234 + ... + 94935.

It is an arithmetic number, because the mean of its divisors is an integer number (6620950).

Almost surely, 2^66398319 is an apocalyptic number.

66398319 is a deficient number, since it is larger than the sum of its proper divisors (39536881).

66398319 is a wasteful number, since it uses less digits than its factorization.

66398319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189191 (or 189185 counting only the distinct ones).

The product of its digits is 209952, while the sum is 45.

The square root of 66398319 is about 8148.5163680268. The cubic root of 66398319 is about 404.9353531932.

The spelling of 66398319 in words is "sixty-six million, three hundred ninety-eight thousand, three hundred nineteen".