28352181 has 16 divisors (see below), whose sum is σ = 44412480. Its totient is φ = 15861120.

The previous prime is 28352173. The next prime is 28352183. The reversal of 28352181 is 18125382.

It is not a de Polignac number, because 28352181 - 2³ = 28352173 is a prime.

It is a super-4 number, since 4×28352181⁴ (a number of 31 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28352183) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32616 + ... + 33473.

It is an arithmetic number, because the mean of its divisors is an integer number (2775780).

Almost surely, 2^28352181 is an apocalyptic number.

It is an amenable number.

28352181 is a deficient number, since it is larger than the sum of its proper divisors (16060299).

28352181 is a wasteful number, since it uses less digits than its factorization.

28352181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66116.

The product of its digits is 3840, while the sum is 30.

The square root of 28352181 is about 5324.6766098985. The cubic root of 28352181 is about 304.9267261048.

The spelling of 28352181 in words is "twenty-eight million, three hundred fifty-two thousand, one hundred eighty-one".