66388222 has 8 divisors (see below), whose sum is σ = 99643536. Its totient is φ = 33173712.

The previous prime is 66388211. The next prime is 66388229. The reversal of 66388222 is 22288366.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66388229) 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, 5743 + ... + 12874.

It is an arithmetic number, because the mean of its divisors is an integer number (12455442).

Almost surely, 2^66388222 is an apocalyptic number.

66388222 is a deficient number, since it is larger than the sum of its proper divisors (33255314).

66388222 is a wasteful number, since it uses less digits than its factorization.

66388222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20402.

The product of its digits is 55296, while the sum is 37.

The square root of 66388222 is about 8147.8967838332. The cubic root of 66388222 is about 404.9148263707.

It can be divided in two parts, 66 and 388222, that multiplied together give a palindrome (25622652).

The spelling of 66388222 in words is "sixty-six million, three hundred eighty-eight thousand, two hundred twenty-two".