261372816 has 60 divisors (see below), whose sum is σ = 769987920. Its totient is φ = 82537920.

The previous prime is 261372763. The next prime is 261372817. The reversal of 261372816 is 618273162.

261372816 is a `hidden beast` number, since 2 + 613 + 7 + 28 + 16 = 666.

261372816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (261372817) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45030 + ... + 50501.

It is an arithmetic number, because the mean of its divisors is an integer number (12833132).

Almost surely, 2^261372816 is an apocalyptic number.

It is an amenable number.

261372816 is an abundant number, since it is smaller than the sum of its proper divisors (508615104).

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

261372816 is a wasteful number, since it uses less digits than its factorization.

261372816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95564 (or 95555 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 261372816 is about 16167.0286694865. The cubic root of 261372816 is about 639.3717924235.

The spelling of 261372816 in words is "two hundred sixty-one million, three hundred seventy-two thousand, eight hundred sixteen".