281161881009 has 81 divisors (see below), whose sum is σ = 444976149891. Its totient is φ = 171036472320.

The previous prime is 281161881001. The next prime is 281161881059. The reversal of 281161881009 is 900188161182.

The square root of 281161881009 is 530247.

It is a perfect power (a square), and thus also a powerful number.

281161881009 is a `hidden beast` number, since 2 + 8 + 11 + 618 + 8 + 10 + 0 + 9 = 666.

It can be written as a sum of positive squares in 13 ways, for example, as 5851791009 + 275310090000 = 76497^2 + 524700^2 .

It is not a de Polignac number, because 281161881009 - 2³ = 281161881001 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (281161881001) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 1000575949 + ... + 1000576229.

Almost surely, 2^281161881009 is an apocalyptic number.

281161881009 is the 530247-th square number.

281161881009 is the 265124-th centered octagonal number.

It is an amenable number.

281161881009 is a deficient number, since it is larger than the sum of its proper divisors (163814268882).

281161881009 is an equidigital number, since it uses as much as digits as its factorization.

281161881009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 676 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 45.

The spelling of 281161881009 in words is "two hundred eighty-one billion, one hundred sixty-one million, eight hundred eighty-one thousand, nine".