266822021 has 4 divisors (see below), whose sum is σ = 282517452. Its totient is φ = 251126592.

The previous prime is 266821999. The next prime is 266822033. The reversal of 266822021 is 120228662.

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 79405921 + 187416100 = 8911^2 + 13690^2 .

It is a cyclic number.

It is not a de Polignac number, because 266822021 - 2¹⁰ = 266820997 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 (266822321) 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, 7847690 + ... + 7847723.

It is an arithmetic number, because the mean of its divisors is an integer number (70629363).

Almost surely, 2^266822021 is an apocalyptic number.

It is an amenable number.

266822021 is a deficient number, since it is larger than the sum of its proper divisors (15695431).

266822021 is a wasteful number, since it uses less digits than its factorization.

266822021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15695430.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 266822021 is about 16334.6876615379. The cubic root of 266822021 is about 643.7845596050.

The spelling of 266822021 in words is "two hundred sixty-six million, eight hundred twenty-two thousand, twenty-one".