66341221 has 4 divisors (see below), whose sum is σ = 67428844. Its totient is φ = 65253600.

The previous prime is 66341203. The next prime is 66341237. The reversal of 66341221 is 12214366.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2117025 + 64224196 = 1455^2 + 8014^2 .

It is a cyclic number.

It is not a de Polignac number, because 66341221 - 2⁹ = 66340709 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 (66341201) 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, 543720 + ... + 543841.

It is an arithmetic number, because the mean of its divisors is an integer number (16857211).

Almost surely, 2^66341221 is an apocalyptic number.

66341221 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

66341221 is a deficient number, since it is larger than the sum of its proper divisors (1087623).

66341221 is a wasteful number, since it uses less digits than its factorization.

66341221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1087622.

The product of its digits is 1728, while the sum is 25.

The square root of 66341221 is about 8145.0120319125. The cubic root of 66341221 is about 404.8192476963.

Adding to 66341221 its reverse (12214366), we get a palindrome (78555587).

The spelling of 66341221 in words is "sixty-six million, three hundred forty-one thousand, two hundred twenty-one".