261646730040404 has 12 divisors (see below), whose sum is σ = 473670804383700. Its totient is φ = 126312214502208.

The previous prime is 261646730040361. The next prime is 261646730040473. The reversal of 261646730040404 is 404040037646162.

It can be written as a sum of positive squares in 2 ways, for example, as 63068184636304 + 198578545404100 = 7941548^2 + 14091790^2 .

It is a super-2 number, since 2×261646730040404² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1127787629369 + ... + 1127787629600.

It is an arithmetic number, because the mean of its divisors is an integer number (39472567031975).

Almost surely, 2^{261646730040404} is an apocalyptic number.

It is an amenable number.

261646730040404 is a deficient number, since it is larger than the sum of its proper divisors (212024074343296).

261646730040404 is a wasteful number, since it uses less digits than its factorization.

261646730040404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2255575259002 (or 2255575259000 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 47.

Adding to 261646730040404 its reverse (404040037646162), we get a palindrome (665686767686566).

The spelling of 261646730040404 in words is "two hundred sixty-one trillion, six hundred forty-six billion, seven hundred thirty million, forty thousand, four hundred four".