261898128 has 60 divisors (see below), whose sum is σ = 771535440. Its totient is φ = 82703808.

The previous prime is 261898111. The next prime is 261898139. The reversal of 261898128 is 821898162.

It is a happy number.

261898128 is a `hidden beast` number, since 2 + 618 + 9 + 8 + 1 + 28 = 666.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45126 + ... + 50597.

It is an arithmetic number, because the mean of its divisors is an integer number (12858924).

Almost surely, 2^261898128 is an apocalyptic number.

It is an amenable number.

261898128 is an abundant number, since it is smaller than the sum of its proper divisors (509637312).

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

261898128 is a wasteful number, since it uses less digits than its factorization.

261898128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95756 (or 95747 counting only the distinct ones).

The product of its digits is 110592, while the sum is 45.

The square root of 261898128 is about 16183.2669136982. The cubic root of 261898128 is about 639.7998462646.

The spelling of 261898128 in words is "two hundred sixty-one million, eight hundred ninety-eight thousand, one hundred twenty-eight".