266378791 has 4 divisors (see below), whose sum is σ = 304432912. Its totient is φ = 228324672.

The previous prime is 266378771. The next prime is 266378821. The reversal of 266378791 is 197873662.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 266378791 - 2⁵ = 266378759 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266378711) 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, 19027050 + ... + 19027063.

It is an arithmetic number, because the mean of its divisors is an integer number (76108228).

Almost surely, 2^266378791 is an apocalyptic number.

266378791 is a deficient number, since it is larger than the sum of its proper divisors (38054121).

266378791 is an equidigital number, since it uses as much as digits as its factorization.

266378791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38054120.

The product of its digits is 762048, while the sum is 49.

The square root of 266378791 is about 16321.1148822622. The cubic root of 266378791 is about 643.4278889239.

The spelling of 266378791 in words is "two hundred sixty-six million, three hundred seventy-eight thousand, seven hundred ninety-one".