28727780 has 24 divisors (see below), whose sum is σ = 60455808. Its totient is φ = 11466848.

The previous prime is 28727779. The next prime is 28727801. The reversal of 28727780 is 8772782.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10517 + ... + 12963.

It is an arithmetic number, because the mean of its divisors is an integer number (2518992).

Almost surely, 2^28727780 is an apocalyptic number.

28727780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28727780 is an abundant number, since it is smaller than the sum of its proper divisors (31728028).

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

28727780 is a wasteful number, since it uses less digits than its factorization.

28727780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3043 (or 3041 counting only the distinct ones).

The product of its (nonzero) digits is 87808, while the sum is 41.

The square root of 28727780 is about 5359.8302211917. The cubic root of 28727780 is about 306.2673415142.

The spelling of 28727780 in words is "twenty-eight million, seven hundred twenty-seven thousand, seven hundred eighty".