261676731672 has 96 divisors (see below), whose sum is σ = 726255363600. Its totient is φ = 85084915968.

The previous prime is 261676731661. The next prime is 261676731709. The reversal of 261676731672 is 276137676162.

It is a happy number.

261676731672 is a `hidden beast` number, since 2 + 616 + 7 + 6 + 7 + 3 + 16 + 7 + 2 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 461979 + ... + 858357.

Almost surely, 2^261676731672 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261676731672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (363127681800).

261676731672 is an abundant number, since it is smaller than the sum of its proper divisors (464578631928).

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

261676731672 is a wasteful number, since it uses less digits than its factorization.

261676731672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396617 (or 396610 counting only the distinct ones).

The product of its digits is 5334336, while the sum is 54.

The spelling of 261676731672 in words is "two hundred sixty-one billion, six hundred seventy-six million, seven hundred thirty-one thousand, six hundred seventy-two".