28813978 has 8 divisors (see below), whose sum is σ = 43344468. Its totient is φ = 14365824.

The previous prime is 28813969. The next prime is 28813979. The reversal of 28813978 is 87931882.

It can be written as a sum of positive squares in 2 ways, for example, as 25775929 + 3038049 = 5077^2 + 1743^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (28813979) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19701 + ... + 21112.

Almost surely, 2^28813978 is an apocalyptic number.

28813978 is a deficient number, since it is larger than the sum of its proper divisors (14530490).

28813978 is a wasteful number, since it uses less digits than its factorization.

28813978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41168.

The product of its digits is 193536, while the sum is 46.

The square root of 28813978 is about 5367.8653112760. The cubic root of 28813978 is about 306.5733550907.

It can be divided in two parts, 28813 and 978, that added together give a cube (29791 = 31³).

The spelling of 28813978 in words is "twenty-eight million, eight hundred thirteen thousand, nine hundred seventy-eight".