66221303 has 4 divisors (see below), whose sum is σ = 66457248. Its totient is φ = 65985360.

The previous prime is 66221291. The next prime is 66221317. The reversal of 66221303 is 30312266.

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 66221303 - 2⁸ = 66221047 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 (66221003) 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, 117551 + ... + 118112.

It is an arithmetic number, because the mean of its divisors is an integer number (16614312).

Almost surely, 2^66221303 is an apocalyptic number.

66221303 is a deficient number, since it is larger than the sum of its proper divisors (235945).

66221303 is a wasteful number, since it uses less digits than its factorization.

66221303 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235944.

The product of its (nonzero) digits is 1296, while the sum is 23.

The square root of 66221303 is about 8137.6472644125. The cubic root of 66221303 is about 404.5751842861.

Adding to 66221303 its reverse (30312266), we get a palindrome (96533569).

The spelling of 66221303 in words is "sixty-six million, two hundred twenty-one thousand, three hundred three".