28980640 has 48 divisors (see below), whose sum is σ = 73738728. Its totient is φ = 10699776.

The previous prime is 28980613. The next prime is 28980641. The reversal of 28980640 is 4608982.

It can be written as a sum of positive squares in 4 ways, for example, as 26584336 + 2396304 = 5156^2 + 1548^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 28980640.

It is not an unprimeable number, because it can be changed into a prime (28980641) 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, 4887 + ... + 9046.

Almost surely, 2^28980640 is an apocalyptic number.

28980640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28980640 is an abundant number, since it is smaller than the sum of its proper divisors (44758088).

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

28980640 is a wasteful number, since it uses less digits than its factorization.

28980640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13961 (or 13953 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 28980640 is about 5383.3669761591. The cubic root of 28980640 is about 307.1632994713.

The spelling of 28980640 in words is "twenty-eight million, nine hundred eighty thousand, six hundred forty".