261265128 has 16 divisors (see below), whose sum is σ = 653162880. Its totient is φ = 87088368.

The previous prime is 261265127. The next prime is 261265133. The reversal of 261265128 is 821562162.

261265128 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (261265127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5443000 + ... + 5443047.

It is an arithmetic number, because the mean of its divisors is an integer number (40822680).

Almost surely, 2^261265128 is an apocalyptic number.

It is an amenable number.

261265128 is an abundant number, since it is smaller than the sum of its proper divisors (391897752).

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

261265128 is a wasteful number, since it uses less digits than its factorization.

261265128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10886056 (or 10886052 counting only the distinct ones).

The product of its digits is 11520, while the sum is 33.

The square root of 261265128 is about 16163.6978442434. The cubic root of 261265128 is about 639.2839713451.

The spelling of 261265128 in words is "two hundred sixty-one million, two hundred sixty-five thousand, one hundred twenty-eight".