888981921 has 12 divisors (see below), whose sum is σ = 1328364180. Its totient is φ = 572218080.

The previous prime is 888981913. The next prime is 888981931. The reversal of 888981921 is 129189888.

It can be written as a sum of positive squares in 2 ways, for example, as 301404321 + 587577600 = 17361^2 + 24240^2 .

It is not a de Polignac number, because 888981921 - 2³ = 888981913 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (888981931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1702770 + ... + 1703291.

It is an arithmetic number, because the mean of its divisors is an integer number (110697015).

Almost surely, 2^888981921 is an apocalyptic number.

It is an amenable number.

888981921 is a deficient number, since it is larger than the sum of its proper divisors (439382259).

888981921 is a wasteful number, since it uses less digits than its factorization.

888981921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3406096 (or 3406093 counting only the distinct ones).

The product of its digits is 663552, while the sum is 54.

The square root of 888981921 is about 29815.7998551104. The cubic root of 888981921 is about 961.5332562487.

It can be divided in two parts, 88 and 8981921, that added together give a square (8982009 = 2997²).

The spelling of 888981921 in words is "eight hundred eighty-eight million, nine hundred eighty-one thousand, nine hundred twenty-one".