28191678 has 16 divisors (see below), whose sum is σ = 59700240. Its totient is φ = 8844416.

The previous prime is 28191677. The next prime is 28191727. The reversal of 28191678 is 87619182.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28191671) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 138093 + ... + 138296.

It is an arithmetic number, because the mean of its divisors is an integer number (3731265).

Almost surely, 2^28191678 is an apocalyptic number.

28191678 is an abundant number, since it is smaller than the sum of its proper divisors (31508562).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28191678 is a wasteful number, since it uses less digits than its factorization.

28191678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276411.

The product of its digits is 48384, while the sum is 42.

The square root of 28191678 is about 5309.5835994925. The cubic root of 28191678 is about 304.3502354811.

The spelling of 28191678 in words is "twenty-eight million, one hundred ninety-one thousand, six hundred seventy-eight".