66403243 has 4 divisors (see below), whose sum is σ = 68693040. Its totient is φ = 64113448.

The previous prime is 66403229. The next prime is 66403273. The reversal of 66403243 is 34230466.

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 66403243 - 2¹³ = 66395051 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66403273) 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, 1144855 + ... + 1144912.

It is an arithmetic number, because the mean of its divisors is an integer number (17173260).

Almost surely, 2^66403243 is an apocalyptic number.

66403243 is a deficient number, since it is larger than the sum of its proper divisors (2289797).

66403243 is a wasteful number, since it uses less digits than its factorization.

66403243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2289796.

The product of its (nonzero) digits is 10368, while the sum is 28.

The square root of 66403243 is about 8148.8185033169. The cubic root of 66403243 is about 404.9453627457.

The spelling of 66403243 in words is "sixty-six million, four hundred three thousand, two hundred forty-three".