266993221 has 16 divisors (see below), whose sum is σ = 299996928. Its totient is φ = 235483200.

The previous prime is 266993213. The next prime is 266993239. The reversal of 266993221 is 122399662.

It is a cyclic number.

It is not a de Polignac number, because 266993221 - 2³ = 266993213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266993261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 186916 + ... + 188338.

It is an arithmetic number, because the mean of its divisors is an integer number (18749808).

Almost surely, 2^266993221 is an apocalyptic number.

It is an amenable number.

266993221 is a deficient number, since it is larger than the sum of its proper divisors (33003707).

266993221 is a wasteful number, since it uses less digits than its factorization.

266993221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1932.

The product of its digits is 69984, while the sum is 40.

The square root of 266993221 is about 16339.9272030202. The cubic root of 266993221 is about 643.9222198478.

The spelling of 266993221 in words is "two hundred sixty-six million, nine hundred ninety-three thousand, two hundred twenty-one".