28109736 has 24 divisors (see below), whose sum is σ = 76130730. Its totient is φ = 9369888.

The previous prime is 28109651. The next prime is 28109747. The reversal of 28109736 is 63790182.

It can be written as a sum of positive squares in only one way, i.e., 25948836 + 2160900 = 5094^2 + 1470^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-3 number, since 3×28109736³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 28109736.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 195135 + ... + 195278.

Almost surely, 2^28109736 is an apocalyptic number.

It is an amenable number.

28109736 is an abundant number, since it is smaller than the sum of its proper divisors (48020994).

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

28109736 is a wasteful number, since it uses less digits than its factorization.

28109736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390425 (or 390418 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 28109736 is about 5301.8615598674. The cubic root of 28109736 is about 304.0550742785.

The spelling of 28109736 in words is "twenty-eight million, one hundred nine thousand, seven hundred thirty-six".