261597172116 has 192 divisors, whose sum is σ = 776299991040. Its totient is φ = 66801715200.

The previous prime is 261597172097. The next prime is 261597172157. The reversal of 261597172116 is 611271795162.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4536666 + ... + 4593966.

It is an arithmetic number, because the mean of its divisors is an integer number (4043229120).

Almost surely, 2^261597172116 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 261597172116, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (388149995520).

261597172116 is an abundant number, since it is smaller than the sum of its proper divisors (514702818924).

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

261597172116 is a wasteful number, since it uses less digits than its factorization.

261597172116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57494 (or 57492 counting only the distinct ones).

The product of its digits is 317520, while the sum is 48.

The spelling of 261597172116 in words is "two hundred sixty-one billion, five hundred ninety-seven million, one hundred seventy-two thousand, one hundred sixteen".