261431337533756 has 144 divisors (see below), whose sum is σ = 544353362380800. Its totient is φ = 109299506823936.

The previous prime is 261431337533701. The next prime is 261431337533797. The reversal of 261431337533756 is 657335733134162.

It is a junction number, because it is equal to n+sod(n) for n = 261431337533695 and 261431337533704.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 803062490 + ... + 803387966.

It is an arithmetic number, because the mean of its divisors is an integer number (3780231683200).

Almost surely, 2^{261431337533756} is an apocalyptic number.

261431337533756 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

261431337533756 is an abundant number, since it is smaller than the sum of its proper divisors (282922024847044).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261431337533756 is a wasteful number, since it uses less digits than its factorization.

261431337533756 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328268 (or 328253 counting only the distinct ones).

The product of its digits is 85730400, while the sum is 59.

The spelling of 261431337533756 in words is "two hundred sixty-one trillion, four hundred thirty-one billion, three hundred thirty-seven million, five hundred thirty-three thousand, seven hundred fifty-six".