261761411515747 has 32 divisors (see below), whose sum is σ = 312124063797504. Its totient is φ = 216374307177600.

The previous prime is 261761411515661. The next prime is 261761411515763. The reversal of 261761411515747 is 747515114167162.

It is a happy number.

It is not a de Polignac number, because 261761411515747 - 2³⁵ = 261727051777379 is a prime.

It is a super-2 number, since 2×261761411515747² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261761411515691 and 261761411515700.

It is not an unprimeable number, because it can be changed into a prime (261761411515847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 301665273 + ... + 302531749.

It is an arithmetic number, because the mean of its divisors is an integer number (9753876993672).

Almost surely, 2^{261761411515747} is an apocalyptic number.

261761411515747 is a deficient number, since it is larger than the sum of its proper divisors (50362652281757).

261761411515747 is a wasteful number, since it uses less digits than its factorization.

261761411515747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 898099.

The product of its digits is 9878400, while the sum is 58.

The spelling of 261761411515747 in words is "two hundred sixty-one trillion, seven hundred sixty-one billion, four hundred eleven million, five hundred fifteen thousand, seven hundred forty-seven".