28756780 has 24 divisors (see below), whose sum is σ = 65035152. Its totient is φ = 10617792.

The previous prime is 28756771. The next prime is 28756781. The reversal of 28756780 is 8765782.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (28756781) 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, 55042 + ... + 55561.

It is an arithmetic number, because the mean of its divisors is an integer number (2709798).

Almost surely, 2^28756780 is an apocalyptic number.

28756780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28756780 is an abundant number, since it is smaller than the sum of its proper divisors (36278372).

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

28756780 is a wasteful number, since it uses less digits than its factorization.

28756780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110625 (or 110623 counting only the distinct ones).

The product of its (nonzero) digits is 188160, while the sum is 43.

The square root of 28756780 is about 5362.5348483716. The cubic root of 28756780 is about 306.3703633504.

The spelling of 28756780 in words is "twenty-eight million, seven hundred fifty-six thousand, seven hundred eighty".