28031280 has 40 divisors (see below), whose sum is σ = 86897712. Its totient is φ = 7474944.

The previous prime is 28031279. The next prime is 28031281. The reversal of 28031280 is 8213082.

It is an interprime number because it is at equal distance from previous prime (28031279) and next prime (28031281).

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 28031280.

It is not an unprimeable number, because it can be changed into a prime (28031281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58159 + ... + 58638.

Almost surely, 2^28031280 is an apocalyptic number.

28031280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28031280 is an abundant number, since it is smaller than the sum of its proper divisors (58866432).

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

28031280 is a wasteful number, since it uses less digits than its factorization.

28031280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116813 (or 116807 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 28031280 is about 5294.4574792891. The cubic root of 28031280 is about 303.7719318954.

The spelling of 28031280 in words is "twenty-eight million, thirty-one thousand, two hundred eighty".