662123221 has 2 divisors, whose sum is σ = 662123222. Its totient is φ = 662123220.

The previous prime is 662123201. The next prime is 662123257. The reversal of 662123221 is 122321266.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 658179025 + 3944196 = 25655^2 + 1986^2 .

It is a cyclic number.

It is not a de Polignac number, because 662123221 - 2⁷ = 662123093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (662123201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331061610 + 331061611.

It is an arithmetic number, because the mean of its divisors is an integer number (331061611).

Almost surely, 2^662123221 is an apocalyptic number.

It is an amenable number.

662123221 is a deficient number, since it is larger than the sum of its proper divisors (1).

662123221 is an equidigital number, since it uses as much as digits as its factorization.

662123221 is an evil number, because the sum of its binary digits is even.

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

The square root of 662123221 is about 25731.7551092031. The cubic root of 662123221 is about 871.5914065923.

Adding to 662123221 its reverse (122321266), we get a palindrome (784444487).

The spelling of 662123221 in words is "six hundred sixty-two million, one hundred twenty-three thousand, two hundred twenty-one".