261319728 has 20 divisors (see below), whose sum is σ = 675076088. Its totient is φ = 87106560.

The previous prime is 261319727. The next prime is 261319757. The reversal of 261319728 is 827913162.

261319728 is digitally balanced in base 2, 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 (261319727) 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, 2722033 + ... + 2722128.

Almost surely, 2^261319728 is an apocalyptic number.

It is an amenable number.

261319728 is an abundant number, since it is smaller than the sum of its proper divisors (413756360).

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

261319728 is a wasteful number, since it uses less digits than its factorization.

261319728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5444172 (or 5444166 counting only the distinct ones).

The product of its digits is 36288, while the sum is 39.

The square root of 261319728 is about 16165.3867259648. The cubic root of 261319728 is about 639.3285014282.

The spelling of 261319728 in words is "two hundred sixty-one million, three hundred nineteen thousand, seven hundred twenty-eight".