66673399 has 4 divisors (see below), whose sum is σ = 71802136. Its totient is φ = 61544664.

The previous prime is 66673361. The next prime is 66673403. The reversal of 66673399 is 99337666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99337666 = 2 ⋅49668833.

It is a cyclic number.

It is not a de Polignac number, because 66673399 - 2¹¹ = 66671351 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 (66673499) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2564349 + ... + 2564374.

It is an arithmetic number, because the mean of its divisors is an integer number (17950534).

Almost surely, 2^66673399 is an apocalyptic number.

66673399 is a deficient number, since it is larger than the sum of its proper divisors (5128737).

66673399 is a wasteful number, since it uses less digits than its factorization.

66673399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5128736.

The product of its digits is 1102248, while the sum is 49.

The square root of 66673399 is about 8165.3780684057. The cubic root of 66673399 is about 405.4937817159.

The spelling of 66673399 in words is "sixty-six million, six hundred seventy-three thousand, three hundred ninety-nine".