28901380 has 24 divisors (see below), whose sum is σ = 61051032. Its totient is φ = 11492352.

The previous prime is 28901311. The next prime is 28901387. The reversal of 28901380 is 8310982.

It can be written as a sum of positive squares in 4 ways, for example, as 10394176 + 18507204 = 3224^2 + 4302^2 .

It is not an unprimeable number, because it can be changed into a prime (28901387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 717 + ... + 7636.

It is an arithmetic number, because the mean of its divisors is an integer number (2543793).

Almost surely, 2^28901380 is an apocalyptic number.

28901380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28901380 is an abundant number, since it is smaller than the sum of its proper divisors (32149652).

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

28901380 is a wasteful number, since it uses less digits than its factorization.

28901380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8535 (or 8533 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 28901380 is about 5376.0003720238. Note that the first 3 decimals coincide. The cubic root of 28901380 is about 306.8830205040.

The spelling of 28901380 in words is "twenty-eight million, nine hundred one thousand, three hundred eighty".