28778132 has 12 divisors (see below), whose sum is σ = 50861076. Its totient is φ = 14246400.

The previous prime is 28778111. The next prime is 28778171. The reversal of 28778132 is 23187782.

It can be written as a sum of positive squares in 2 ways, for example, as 24960016 + 3818116 = 4996^2 + 1954^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35213 + ... + 36020.

It is an arithmetic number, because the mean of its divisors is an integer number (4238423).

Almost surely, 2^28778132 is an apocalyptic number.

It is an amenable number.

28778132 is a deficient number, since it is larger than the sum of its proper divisors (22082944).

28778132 is a wasteful number, since it uses less digits than its factorization.

28778132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71338 (or 71336 counting only the distinct ones).

The product of its digits is 37632, while the sum is 38.

The square root of 28778132 is about 5364.5253284890. The cubic root of 28778132 is about 306.4461715785.

The spelling of 28778132 in words is "twenty-eight million, seven hundred seventy-eight thousand, one hundred thirty-two".