66222621 has 12 divisors (see below), whose sum is σ = 96550272. Its totient is φ = 43735176.

The previous prime is 66222617. The next prime is 66222641. The reversal of 66222621 is 12622266.

It is not a de Polignac number, because 66222621 - 2² = 66222617 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66222601) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33421 + ... + 35346.

It is an arithmetic number, because the mean of its divisors is an integer number (8045856).

Almost surely, 2^66222621 is an apocalyptic number.

It is an amenable number.

66222621 is a deficient number, since it is larger than the sum of its proper divisors (30327651).

66222621 is a wasteful number, since it uses less digits than its factorization.

66222621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68880 (or 68877 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 66222621 is about 8137.7282456469. The cubic root of 66222621 is about 404.5778683496.

Adding to 66222621 its reverse (12622266), we get a palindrome (78844887).

The spelling of 66222621 in words is "sixty-six million, two hundred twenty-two thousand, six hundred twenty-one".