28179581 has 2 divisors, whose sum is σ = 28179582. Its totient is φ = 28179580.

The previous prime is 28179563. The next prime is 28179617. The reversal of 28179581 is 18597182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27994681 + 184900 = 5291^2 + 430^2 .

It is a cyclic number.

It is not a de Polignac number, because 28179581 - 2¹⁴ = 28163197 is a prime.

It is a super-2 number, since 2×28179581² = 1588177570671122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28179511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14089790 + 14089791.

It is an arithmetic number, because the mean of its divisors is an integer number (14089791).

Almost surely, 2^28179581 is an apocalyptic number.

It is an amenable number.

28179581 is a deficient number, since it is larger than the sum of its proper divisors (1).

28179581 is an equidigital number, since it uses as much as digits as its factorization.

28179581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40320, while the sum is 41.

The square root of 28179581 is about 5308.4443107185. Note that the first 3 decimals coincide. The cubic root of 28179581 is about 304.3066972008.

The spelling of 28179581 in words is "twenty-eight million, one hundred seventy-nine thousand, five hundred eighty-one".