28131435280 has 40 divisors (see below), whose sum is σ = 70436788632. Its totient is φ = 10386991104.

The previous prime is 28131435251. The next prime is 28131435281. The reversal of 28131435280 is 8253413182.

It can be written as a sum of positive squares in 4 ways, for example, as 281165824 + 27850269456 = 16768^2 + 166884^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (28131435281) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13523689 + ... + 13525768.

Almost surely, 2^28131435280 is an apocalyptic number.

28131435280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28131435280 is an abundant number, since it is smaller than the sum of its proper divisors (42305353352).

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

28131435280 is a wasteful number, since it uses less digits than its factorization.

28131435280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27049483 (or 27049477 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 37.

The spelling of 28131435280 in words is "twenty-eight billion, one hundred thirty-one million, four hundred thirty-five thousand, two hundred eighty".