28290278 has 16 divisors (see below), whose sum is σ = 47297520. Its totient is φ = 12612096.

The previous prime is 28290271. The next prime is 28290307. The reversal of 28290278 is 87209282.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28290271) 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, 21251 + ... + 22542.

It is an arithmetic number, because the mean of its divisors is an integer number (2956095).

Almost surely, 2^28290278 is an apocalyptic number.

28290278 is a deficient number, since it is larger than the sum of its proper divisors (19007242).

28290278 is a wasteful number, since it uses less digits than its factorization.

28290278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43831.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 28290278 is about 5318.8605922697. The cubic root of 28290278 is about 304.7046428558.

The spelling of 28290278 in words is "twenty-eight million, two hundred ninety thousand, two hundred seventy-eight".