28180393 has 2 divisors, whose sum is σ = 28180394. Its totient is φ = 28180392.

The previous prime is 28180391. The next prime is 28180459. The reversal of 28180393 is 39308182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15705369 + 12475024 = 3963^2 + 3532^2 .

It is a cyclic number.

It is not a de Polignac number, because 28180393 - 2¹ = 28180391 is a prime.

Together with 28180391, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28180391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14090196 + 14090197.

It is an arithmetic number, because the mean of its divisors is an integer number (14090197).

Almost surely, 2^28180393 is an apocalyptic number.

It is an amenable number.

28180393 is a deficient number, since it is larger than the sum of its proper divisors (1).

28180393 is an equidigital number, since it uses as much as digits as its factorization.

28180393 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 28180393 is about 5308.5207920851. The cubic root of 28180393 is about 304.3096200579.

The spelling of 28180393 in words is "twenty-eight million, one hundred eighty thousand, three hundred ninety-three".