28640124081 has 12 divisors (see below), whose sum is σ = 41386770100. Its totient is φ = 19085245920.

The previous prime is 28640124061. The next prime is 28640124089. The reversal of 28640124081 is 18042104682.

28640124081 is a `hidden beast` number, since 2 + 8 + 6 + 401 + 240 + 8 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 21722043456 + 6918080625 = 147384^2 + 83175^2 .

It is not a de Polignac number, because 28640124081 - 2²¹ = 28638026929 is a prime.

It is a super-2 number, since 2×28640124081² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28640124089) 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, 658606 + ... + 700743.

Almost surely, 2^28640124081 is an apocalyptic number.

It is an amenable number.

28640124081 is a deficient number, since it is larger than the sum of its proper divisors (12746646019).

28640124081 is a wasteful number, since it uses less digits than its factorization.

28640124081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1361696 (or 1361693 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 36.

The spelling of 28640124081 in words is "twenty-eight billion, six hundred forty million, one hundred twenty-four thousand, eighty-one".