266411221 has 2 divisors, whose sum is σ = 266411222. Its totient is φ = 266411220.

The previous prime is 266411191. The next prime is 266411239. The reversal of 266411221 is 122114662.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 228342321 + 38068900 = 15111^2 + 6170^2 .

It is a cyclic number.

It is not a de Polignac number, because 266411221 - 2¹¹ = 266409173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (266411261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133205610 + 133205611.

It is an arithmetic number, because the mean of its divisors is an integer number (133205611).

Almost surely, 2^266411221 is an apocalyptic number.

It is an amenable number.

266411221 is a deficient number, since it is larger than the sum of its proper divisors (1).

266411221 is an equidigital number, since it uses as much as digits as its factorization.

266411221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 25.

The square root of 266411221 is about 16322.1083503327. The cubic root of 266411221 is about 643.4539990103.

Adding to 266411221 its reverse (122114662), we get a palindrome (388525883).

The spelling of 266411221 in words is "two hundred sixty-six million, four hundred eleven thousand, two hundred twenty-one".