266408621 has 4 divisors (see below), whose sum is σ = 273608892. Its totient is φ = 259208352.

The previous prime is 266408579. The next prime is 266408627. The reversal of 266408621 is 126804662.

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 136562596 + 129846025 = 11686^2 + 11395^2 .

It is a cyclic number.

It is not a de Polignac number, because 266408621 - 2²⁶ = 199299757 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 (266408627) 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, 3600080 + ... + 3600153.

It is an arithmetic number, because the mean of its divisors is an integer number (68402223).

Almost surely, 2^266408621 is an apocalyptic number.

It is an amenable number.

266408621 is a deficient number, since it is larger than the sum of its proper divisors (7200271).

266408621 is an equidigital number, since it uses as much as digits as its factorization.

266408621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7200270.

The product of its (nonzero) digits is 27648, while the sum is 35.

The square root of 266408621 is about 16322.0287035650. The cubic root of 266408621 is about 643.4519057728.

The spelling of 266408621 in words is "two hundred sixty-six million, four hundred eight thousand, six hundred twenty-one".