266531036500261 has 8 divisors (see below), whose sum is σ = 292449148903800. Its totient is φ = 241386599093952.

The previous prime is 266531036500247. The next prime is 266531036500277. The reversal of 266531036500261 is 162005630135662.

It can be written as a sum of positive squares in 4 ways, for example, as 3212586632161 + 263318449868100 = 1792369^2 + 16227090^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 266531036500261 - 2⁷ = 266531036500133 is a prime.

It is a super-2 number, since 2×266531036500261² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266531036500231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 193418748586 + ... + 193418749963.

It is an arithmetic number, because the mean of its divisors is an integer number (36556143612975).

Almost surely, 2^{266531036500261} is an apocalyptic number.

It is an amenable number.

266531036500261 is a deficient number, since it is larger than the sum of its proper divisors (25918112403539).

266531036500261 is a wasteful number, since it uses less digits than its factorization.

266531036500261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386837498615.

The product of its (nonzero) digits is 1166400, while the sum is 46.

The spelling of 266531036500261 in words is "two hundred sixty-six trillion, five hundred thirty-one billion, thirty-six million, five hundred thousand, two hundred sixty-one".