28227978 has 12 divisors (see below), whose sum is σ = 61160658. Its totient is φ = 9409320.

The previous prime is 28227961. The next prime is 28227989. The reversal of 28227978 is 87972282.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 28227969 + 9 = 5313^2 + 3^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 784093 + ... + 784128.

Almost surely, 2^28227978 is an apocalyptic number.

28227978 is an abundant number, since it is smaller than the sum of its proper divisors (32932680).

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

28227978 is a wasteful number, since it uses less digits than its factorization.

28227978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1568229 (or 1568226 counting only the distinct ones).

The product of its digits is 225792, while the sum is 45.

The square root of 28227978 is about 5313.0008469790. Note that the first 3 decimals coincide. The cubic root of 28227978 is about 304.4808079987.

The spelling of 28227978 in words is "twenty-eight million, two hundred twenty-seven thousand, nine hundred seventy-eight".