66707399 has 4 divisors (see below), whose sum is σ = 72771720. Its totient is φ = 60643080.

The previous prime is 66707359. The next prime is 66707413. The reversal of 66707399 is 99370766.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66707399 - 2¹² = 66703303 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 (66707359) 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, 3032144 + ... + 3032165.

It is an arithmetic number, because the mean of its divisors is an integer number (18192930).

Almost surely, 2^66707399 is an apocalyptic number.

66707399 is a deficient number, since it is larger than the sum of its proper divisors (6064321).

66707399 is a wasteful number, since it uses less digits than its factorization.

66707399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6064320.

The product of its (nonzero) digits is 428652, while the sum is 47.

The square root of 66707399 is about 8167.4597642107. The cubic root of 66707399 is about 405.5626969851.

The spelling of 66707399 in words is "sixty-six million, seven hundred seven thousand, three hundred ninety-nine".