261826547816 has 8 divisors (see below), whose sum is σ = 490924777170. Its totient is φ = 130913273904.

The previous prime is 261826547809. The next prime is 261826547819. The reversal of 261826547816 is 618745628162.

261826547816 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 219542850916 + 42283696900 = 468554^2 + 205630^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×261826547816² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (261826547819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16364159231 + ... + 16364159246.

Almost surely, 2^261826547816 is an apocalyptic number.

It is an amenable number.

261826547816 is a deficient number, since it is larger than the sum of its proper divisors (229098229354).

261826547816 is a wasteful number, since it uses less digits than its factorization.

261826547816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32728318483 (or 32728318479 counting only the distinct ones).

The product of its digits is 7741440, while the sum is 56.

The spelling of 261826547816 in words is "two hundred sixty-one billion, eight hundred twenty-six million, five hundred forty-seven thousand, eight hundred sixteen".