28734880 has 24 divisors (see below), whose sum is σ = 67886532. Its totient is φ = 11493888.

The previous prime is 28734869. The next prime is 28734887. The reversal of 28734880 is 8843782.

It can be written as a sum of positive squares in 2 ways, for example, as 27836176 + 898704 = 5276^2 + 948^2 .

It is a super-2 number, since 2×28734880² = 1651386657228800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (28734887) 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 3 ways as a sum of consecutive naturals, for example, 89637 + ... + 89956.

Almost surely, 2^28734880 is an apocalyptic number.

28734880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28734880 is an abundant number, since it is smaller than the sum of its proper divisors (39151652).

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

28734880 is a wasteful number, since it uses less digits than its factorization.

28734880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179608 (or 179600 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 40.

The square root of 28734880 is about 5360.4925146856. The cubic root of 28734880 is about 306.2925705087.

The spelling of 28734880 in words is "twenty-eight million, seven hundred thirty-four thousand, eight hundred eighty".