28956780 has 72 divisors (see below), whose sum is σ = 93012192. Its totient is φ = 7266816.

The previous prime is 28956757. The next prime is 28956827. The reversal of 28956780 is 8765982.

28956780 is a `hidden beast` number, since 2 + 8 + 9 + 567 + 80 = 666.

It is a Smith number, since the sum of its digits (45) 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 (45).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1672 + ... + 7791.

It is an arithmetic number, because the mean of its divisors is an integer number (1291836).

Almost surely, 2^28956780 is an apocalyptic number.

28956780 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 28956780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46506096).

28956780 is an abundant number, since it is smaller than the sum of its proper divisors (64055412).

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

28956780 is a wasteful number, since it uses less digits than its factorization.

28956780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9495 (or 9490 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The square root of 28956780 is about 5381.1504346190. The cubic root of 28956780 is about 307.0789796338.

The spelling of 28956780 in words is "twenty-eight million, nine hundred fifty-six thousand, seven hundred eighty".