28381972 has 12 divisors (see below), whose sum is σ = 52282720. Its totient is φ = 13444056.

The previous prime is 28381939. The next prime is 28381973. The reversal of 28381972 is 27918382.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28381973) 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, 186648 + ... + 186799.

Almost surely, 2^28381972 is an apocalyptic number.

It is an amenable number.

28381972 is a deficient number, since it is larger than the sum of its proper divisors (23900748).

28381972 is a wasteful number, since it uses less digits than its factorization.

28381972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 373470 (or 373468 counting only the distinct ones).

The product of its digits is 48384, while the sum is 40.

The square root of 28381972 is about 5327.4733223171. The cubic root of 28381972 is about 305.0334891114.

The spelling of 28381972 in words is "twenty-eight million, three hundred eighty-one thousand, nine hundred seventy-two".