28731384 has 48 divisors (see below), whose sum is σ = 84890520. Its totient is φ = 8706240.

The previous prime is 28731383. The next prime is 28731403. The reversal of 28731384 is 48313782.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28731383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17347 + ... + 18930.

Almost surely, 2^28731384 is an apocalyptic number.

28731384 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

28731384 is an abundant number, since it is smaller than the sum of its proper divisors (56159136).

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

28731384 is a wasteful number, since it uses less digits than its factorization.

28731384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36300 (or 36293 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 28731384 is about 5360.1664153270. The cubic root of 28731384 is about 306.2801484133.

The spelling of 28731384 in words is "twenty-eight million, seven hundred thirty-one thousand, three hundred eighty-four".