261265872 has 80 divisors (see below), whose sum is σ = 797984640. Its totient is φ = 72070656.

The previous prime is 261265847. The next prime is 261265889. The reversal of 261265872 is 278562162.

261265872 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 261265872.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3663 + ... + 23150.

It is an arithmetic number, because the mean of its divisors is an integer number (9974808).

Almost surely, 2^261265872 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 261265872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (398992320).

261265872 is an abundant number, since it is smaller than the sum of its proper divisors (536718768).

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

261265872 is a wasteful number, since it uses less digits than its factorization.

261265872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26860 (or 26854 counting only the distinct ones).

The product of its digits is 80640, while the sum is 39.

The square root of 261265872 is about 16163.7208587627. The cubic root of 261265872 is about 639.2845781703.

The spelling of 261265872 in words is "two hundred sixty-one million, two hundred sixty-five thousand, eight hundred seventy-two".