261578886 has 16 divisors (see below), whose sum is σ = 523686384. Its totient is φ = 87104864.

The previous prime is 261578879. The next prime is 261578917. The reversal of 261578886 is 688875162.

261578886 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15441 + ... + 27596.

It is an arithmetic number, because the mean of its divisors is an integer number (32730399).

Almost surely, 2^261578886 is an apocalyptic number.

261578886 is an abundant number, since it is smaller than the sum of its proper divisors (262107498).

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

261578886 is a wasteful number, since it uses less digits than its factorization.

261578886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44055.

The product of its digits is 1290240, while the sum is 51.

The square root of 261578886 is about 16173.4005700718. The cubic root of 261578886 is about 639.5397781849.

The spelling of 261578886 in words is "two hundred sixty-one million, five hundred seventy-eight thousand, eight hundred eighty-six".