28180433 has 4 divisors (see below), whose sum is σ = 28336308. Its totient is φ = 28024560.

The previous prime is 28180393. The next prime is 28180459. The reversal of 28180433 is 33408182.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4870849 + 23309584 = 2207^2 + 4828^2 .

It is a cyclic number.

It is not a de Polignac number, because 28180433 - 2⁸ = 28180177 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28180396 and 28180405.

It is not an unprimeable number, because it can be changed into a prime (28182433) 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, 77666 + ... + 78027.

It is an arithmetic number, because the mean of its divisors is an integer number (7084077).

Almost surely, 2^28180433 is an apocalyptic number.

It is an amenable number.

28180433 is a deficient number, since it is larger than the sum of its proper divisors (155875).

28180433 is a wasteful number, since it uses less digits than its factorization.

28180433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155874.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 28180433 is about 5308.5245596116. The cubic root of 28180433 is about 304.3097640396.

The spelling of 28180433 in words is "twenty-eight million, one hundred eighty thousand, four hundred thirty-three".