28811698209 has 36 divisors (see below), whose sum is σ = 51259241124. Its totient is φ = 15495363072.

The previous prime is 28811698187. The next prime is 28811698229. The reversal of 28811698209 is 90289611882.

It can be written as a sum of positive squares in 2 ways, for example, as 26099371809 + 2712326400 = 161553^2 + 52080^2 .

It is not a de Polignac number, because 28811698209 - 2⁹ = 28811697697 is a prime.

It is a super-2 number, since 2×28811698209² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28811698229) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1914052 + ... + 1929045.

It is an arithmetic number, because the mean of its divisors is an integer number (1423867809).

Almost surely, 2^28811698209 is an apocalyptic number.

It is an amenable number.

28811698209 is a deficient number, since it is larger than the sum of its proper divisors (22447542915).

28811698209 is a wasteful number, since it uses less digits than its factorization.

28811698209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3843134 (or 3843124 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 54.

It can be divided in two parts, 2881 and 1698209, that added together give a triangular number (1701090 = T₁₈₄₄).

The spelling of 28811698209 in words is "twenty-eight billion, eight hundred eleven million, six hundred ninety-eight thousand, two hundred nine".