28697280 has 112 divisors (see below), whose sum is σ = 92171520. Its totient is φ = 7564288.

The previous prime is 28697257. The next prime is 28697281. The reversal of 28697280 is 8279682.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28697281) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 160231 + ... + 160409.

It is an arithmetic number, because the mean of its divisors is an integer number (822960).

Almost surely, 2^28697280 is an apocalyptic number.

28697280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28697280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46085760).

28697280 is an abundant number, since it is smaller than the sum of its proper divisors (63474240).

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

28697280 is a wasteful number, since it uses less digits than its factorization.

28697280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366 (or 356 counting only the distinct ones).

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

The square root of 28697280 is about 5356.9842262228. The cubic root of 28697280 is about 306.1589161309.

The spelling of 28697280 in words is "twenty-eight million, six hundred ninety-seven thousand, two hundred eighty".