28281278 has 4 divisors (see below), whose sum is σ = 42421920. Its totient is φ = 14140638.

The previous prime is 28281259. The next prime is 28281299. The reversal of 28281278 is 87218282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87218282 = 2 ⋅43609141.

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, 7070318 + ... + 7070321.

It is an arithmetic number, because the mean of its divisors is an integer number (10605480).

Almost surely, 2^28281278 is an apocalyptic number.

28281278 is a deficient number, since it is larger than the sum of its proper divisors (14140642).

28281278 is a wasteful number, since it uses less digits than its factorization.

28281278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14140641.

The product of its digits is 28672, while the sum is 38.

The square root of 28281278 is about 5318.0144791078. The cubic root of 28281278 is about 304.6723274829.

The spelling of 28281278 in words is "twenty-eight million, two hundred eighty-one thousand, two hundred seventy-eight".