28699998988644 has 81 divisors (see below), whose sum is σ = 72965038681899. Its totient is φ = 9511883213760.

The previous prime is 28699998988607. The next prime is 28699998988651. The reversal of 28699998988644 is 44688989999682.

The square root of 28699998988644 is 5357238.

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

28699998988644 is a `hidden beast` number, since 286 + 9 + 99 + 98 + 98 + 8 + 64 + 4 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 16853405984100 + 11846593004544 = 4105290^2 + 3441888^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 5817958002 + ... + 5817962934.

Almost surely, 2^{28699998988644} is an apocalyptic number.

28699998988644 is the 5357238-th square number.

It is an amenable number.

28699998988644 is an abundant number, since it is smaller than the sum of its proper divisors (44265039693255).

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

28699998988644 is an frugal number, since it uses more digits than its factorization.

28699998988644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10238 (or 5119 counting only the distinct ones).

The product of its digits is 278628139008, while the sum is 99.

The spelling of 28699998988644 in words is "twenty-eight trillion, six hundred ninety-nine billion, nine hundred ninety-eight million, nine hundred eighty-eight thousand, six hundred forty-four".