28181995 has 4 divisors (see below), whose sum is σ = 33818400. Its totient is φ = 22545592.

The previous prime is 28181977. The next prime is 28182013. The reversal of 28181995 is 59918182.

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

It is an interprime number because it is at equal distance from previous prime (28181977) and next prime (28182013).

It is a cyclic number.

It is not a de Polignac number, because 28181995 - 2⁵ = 28181963 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2818195 + ... + 2818204.

It is an arithmetic number, because the mean of its divisors is an integer number (8454600).

Almost surely, 2^28181995 is an apocalyptic number.

28181995 is a deficient number, since it is larger than the sum of its proper divisors (5636405).

28181995 is an equidigital number, since it uses as much as digits as its factorization.

28181995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5636404.

The product of its digits is 51840, while the sum is 43.

The square root of 28181995 is about 5308.6716794317. The cubic root of 28181995 is about 304.3153864168.

The spelling of 28181995 in words is "twenty-eight million, one hundred eighty-one thousand, nine hundred ninety-five".