28705488 has 80 divisors (see below), whose sum is σ = 87077760. Its totient is φ = 7976448.

The previous prime is 28705487. The next prime is 28705493. The reversal of 28705488 is 88450782.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28705487) 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, 11278 + ... + 13586.

It is an arithmetic number, because the mean of its divisors is an integer number (1088472).

Almost surely, 2^28705488 is an apocalyptic number.

28705488 is a gapful number since it is divisible by the number (28) 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 28705488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43538880).

28705488 is an abundant number, since it is smaller than the sum of its proper divisors (58372272).

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

28705488 is a wasteful number, since it uses less digits than its factorization.

28705488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2364 (or 2358 counting only the distinct ones).

The product of its (nonzero) digits is 143360, while the sum is 42.

The square root of 28705488 is about 5357.7502741356. The cubic root of 28705488 is about 306.1881025537.

The spelling of 28705488 in words is "twenty-eight million, seven hundred five thousand, four hundred eighty-eight".