28959640 has 64 divisors (see below), whose sum is σ = 67716000. Its totient is φ = 11139072.

The previous prime is 28959631. The next prime is 28959647. The reversal of 28959640 is 4695982.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28959647) 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, 194286 + ... + 194434.

Almost surely, 2^28959640 is an apocalyptic number.

28959640 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 28959640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33858000).

28959640 is an abundant number, since it is smaller than the sum of its proper divisors (38756360).

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

28959640 is a wasteful number, since it uses less digits than its factorization.

28959640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316 (or 312 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 43.

The square root of 28959640 is about 5381.4161704890. The cubic root of 28959640 is about 307.0890891484.

The spelling of 28959640 in words is "twenty-eight million, nine hundred fifty-nine thousand, six hundred forty".