28297136 has 40 divisors (see below), whose sum is σ = 63534624. Its totient is φ = 11957760.

The previous prime is 28297133. The next prime is 28297147. The reversal of 28297136 is 63179282.

It is a self number, because there is not a number n which added to its sum of digits gives 28297136.

It is not an unprimeable number, because it can be changed into a prime (28297133) 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, 6446 + ... + 9906.

Almost surely, 2^28297136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28297136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31767312).

28297136 is an abundant number, since it is smaller than the sum of its proper divisors (35237488).

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

28297136 is a wasteful number, since it uses less digits than its factorization.

28297136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3549 (or 3543 counting only the distinct ones).

The product of its digits is 36288, while the sum is 38.

The square root of 28297136 is about 5319.5052401516. The cubic root of 28297136 is about 304.7292625691.

The spelling of 28297136 in words is "twenty-eight million, two hundred ninety-seven thousand, one hundred thirty-six".