28307980 has 24 divisors (see below), whose sum is σ = 60166512. Its totient is φ = 11186112.

The previous prime is 28307953. The next prime is 28307987. The reversal of 28307980 is 8970382.

It is not an unprimeable number, because it can be changed into a prime (28307987) 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, 6867 + ... + 10186.

It is an arithmetic number, because the mean of its divisors is an integer number (2506938).

Almost surely, 2^28307980 is an apocalyptic number.

28307980 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28307980 is an abundant number, since it is smaller than the sum of its proper divisors (31858532).

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

28307980 is a wasteful number, since it uses less digits than its factorization.

28307980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17145 (or 17143 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 28307980 is about 5320.5244102438. The cubic root of 28307980 is about 304.7681836116.

The spelling of 28307980 in words is "twenty-eight million, three hundred seven thousand, nine hundred eighty".