28691604136 has 16 divisors (see below), whose sum is σ = 57934970100. Its totient is φ = 13242278784.

The previous prime is 28691604119. The next prime is 28691604199. The reversal of 28691604136 is 63140619682.

It can be written as a sum of positive squares in 2 ways, for example, as 28415844900 + 275759236 = 168570^2 + 16606^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137940301 + ... + 137940508.

Almost surely, 2^28691604136 is an apocalyptic number.

28691604136 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

28691604136 is an abundant number, since it is smaller than the sum of its proper divisors (29243365964).

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

28691604136 is a wasteful number, since it uses less digits than its factorization.

28691604136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275880828 (or 275880824 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 46.

The spelling of 28691604136 in words is "twenty-eight billion, six hundred ninety-one million, six hundred four thousand, one hundred thirty-six".