28401140 has 12 divisors (see below), whose sum is σ = 59642436. Its totient is φ = 11360448.

The previous prime is 28401133. The next prime is 28401167. The reversal of 28401140 is 4110482.

It can be written as a sum of positive squares in 2 ways, for example, as 15713296 + 12687844 = 3964^2 + 3562^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1420057 = 28401140 / (2 + 8 + 4 + 0 + 1 + 1 + 4 + 0).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 710009 + ... + 710048.

It is an arithmetic number, because the mean of its divisors is an integer number (4970203).

Almost surely, 2^28401140 is an apocalyptic number.

28401140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28401140 is an abundant number, since it is smaller than the sum of its proper divisors (31241296).

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

28401140 is a wasteful number, since it uses less digits than its factorization.

28401140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1420066 (or 1420064 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 28401140 is about 5329.2719953104. The cubic root of 28401140 is about 305.1021426234.

The spelling of 28401140 in words is "twenty-eight million, four hundred one thousand, one hundred forty".