266195115481 has 3 divisors (see below), whose sum is σ = 266195631423. Its totient is φ = 266194599540.

The previous prime is 266195115457. The next prime is 266195115523. The reversal of 266195115481 is 184511591662.

It is a happy number.

The square root of 266195115481 is 515941.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 70388865481 + 195806250000 = 265309^2 + 442500^2 .

It is not a de Polignac number, because 266195115481 - 2⁷ = 266195115353 is a prime.

It is a super-2 number, since 2×266195115481² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (266195115421) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 257971 + ... + 773911.

It is an arithmetic number, because the mean of its divisors is an integer number (88731877141).

Almost surely, 2^266195115481 is an apocalyptic number.

266195115481 is the 515941-st square number.

266195115481 is the 257971-st centered octagonal number.

It is an amenable number.

266195115481 is a deficient number, since it is larger than the sum of its proper divisors (515942).

266195115481 is an frugal number, since it uses more digits than its factorization.

266195115481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1031882 (or 515941 counting only the distinct ones).

The product of its digits is 518400, while the sum is 49.

Multiplying 266195115481 by its sum of digits (49), we get a square (13043560658569 = 3611587²).

The spelling of 266195115481 in words is "two hundred sixty-six billion, one hundred ninety-five million, one hundred fifteen thousand, four hundred eighty-one".