28261294433 has 4 divisors (see below), whose sum is σ = 28450967700. Its totient is φ = 28071621168.

The previous prime is 28261294381. The next prime is 28261294487. The reversal of 28261294433 is 33449216282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 33449216282 = 2 ⋅16724608141.

It can be written as a sum of positive squares in 2 ways, for example, as 5587861504 + 22673432929 = 74752^2 + 150577^2 .

It is a cyclic number.

It is not a de Polignac number, because 28261294433 - 2¹⁰ = 28261293409 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28261294493) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94836410 + ... + 94836707.

It is an arithmetic number, because the mean of its divisors is an integer number (7112741925).

Almost surely, 2^28261294433 is an apocalyptic number.

It is an amenable number.

28261294433 is a deficient number, since it is larger than the sum of its proper divisors (189673267).

28261294433 is a wasteful number, since it uses less digits than its factorization.

28261294433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189673266.

The product of its digits is 497664, while the sum is 44.

The spelling of 28261294433 in words is "twenty-eight billion, two hundred sixty-one million, two hundred ninety-four thousand, four hundred thirty-three".