28731489 has 8 divisors (see below), whose sum is σ = 39629760. Its totient is φ = 18493776.

The previous prime is 28731487. The next prime is 28731491. The reversal of 28731489 is 98413782.

It is an interprime number because it is at equal distance from previous prime (28731487) and next prime (28731491).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28731489 - 2¹ = 28731487 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28731489.

It is not an unprimeable number, because it can be changed into a prime (28731487) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 165037 + ... + 165210.

It is an arithmetic number, because the mean of its divisors is an integer number (4953720).

Almost surely, 2^28731489 is an apocalyptic number.

28731489 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

28731489 is a deficient number, since it is larger than the sum of its proper divisors (10898271).

28731489 is a wasteful number, since it uses less digits than its factorization.

28731489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330279.

The product of its digits is 96768, while the sum is 42.

The square root of 28731489 is about 5360.1762097901. The cubic root of 28731489 is about 306.2805215173.

The spelling of 28731489 in words is "twenty-eight million, seven hundred thirty-one thousand, four hundred eighty-nine".