266541151276621 has 4 divisors (see below), whose sum is σ = 287044316759452. Its totient is φ = 246037985793792.

The previous prime is 266541151276601. The next prime is 266541151276657. The reversal of 266541151276621 is 126672151145662.

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 83972114776900 + 182569036499721 = 9163630^2 + 13511811^2 .

It is a cyclic number.

It is not a de Polignac number, because 266541151276621 - 2³¹ = 266539003792973 is a prime.

It is a super-2 number, since 2×266541151276621² (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 (266541151276601) 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, 10251582741396 + ... + 10251582741421.

It is an arithmetic number, because the mean of its divisors is an integer number (71761079189863).

Almost surely, 2^{266541151276621} is an apocalyptic number.

It is an amenable number.

266541151276621 is a deficient number, since it is larger than the sum of its proper divisors (20503165482831).

266541151276621 is a wasteful number, since it uses less digits than its factorization.

266541151276621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20503165482830.

The product of its digits is 7257600, while the sum is 55.

The spelling of 266541151276621 in words is "two hundred sixty-six trillion, five hundred forty-one billion, one hundred fifty-one million, two hundred seventy-six thousand, six hundred twenty-one".