28145778 has 16 divisors (see below), whose sum is σ = 59603040. Its totient is φ = 8830016.

The previous prime is 28145723. The next prime is 28145791. The reversal of 28145778 is 87754182.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137868 + ... + 138071.

It is an arithmetic number, because the mean of its divisors is an integer number (3725190).

Almost surely, 2^28145778 is an apocalyptic number.

28145778 is an abundant number, since it is smaller than the sum of its proper divisors (31457262).

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

28145778 is a wasteful number, since it uses less digits than its factorization.

28145778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275961.

The product of its digits is 125440, while the sum is 42.

The square root of 28145778 is about 5305.2594658508. The cubic root of 28145778 is about 304.1849708215.

The spelling of 28145778 in words is "twenty-eight million, one hundred forty-five thousand, seven hundred seventy-eight".