28805278 has 4 divisors (see below), whose sum is σ = 43207920. Its totient is φ = 14402638.

The previous prime is 28805267. The next prime is 28805281. The reversal of 28805278 is 87250882.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87250882 = 2 ⋅43625441.

It is a self number, because there is not a number n which added to its sum of digits gives 28805278.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7201318 + ... + 7201321.

It is an arithmetic number, because the mean of its divisors is an integer number (10801980).

Almost surely, 2^28805278 is an apocalyptic number.

28805278 is a deficient number, since it is larger than the sum of its proper divisors (14402642).

28805278 is a wasteful number, since it uses less digits than its factorization.

28805278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14402641.

The product of its (nonzero) digits is 71680, while the sum is 40.

The square root of 28805278 is about 5367.0548720877. The cubic root of 28805278 is about 306.5424967266.

The spelling of 28805278 in words is "twenty-eight million, eight hundred five thousand, two hundred seventy-eight".