28907140 has 24 divisors (see below), whose sum is σ = 64276632. Its totient is φ = 10882560.

The previous prime is 28907117. The next prime is 28907149. The reversal of 28907140 is 4170982.

It can be written as a sum of positive squares in 4 ways, for example, as 4384836 + 24522304 = 2094^2 + 4952^2 .

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28907149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42171 + ... + 42850.

It is an arithmetic number, because the mean of its divisors is an integer number (2678193).

Almost surely, 2^28907140 is an apocalyptic number.

28907140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28907140 is an abundant number, since it is smaller than the sum of its proper divisors (35369492).

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

28907140 is a wasteful number, since it uses less digits than its factorization.

28907140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85047 (or 85045 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 28907140 is about 5376.5360595833. The cubic root of 28907140 is about 306.9034062524.

The spelling of 28907140 in words is "twenty-eight million, nine hundred seven thousand, one hundred forty".