28087380 has 36 divisors (see below), whose sum is σ = 85198932. Its totient is φ = 7489920.

The previous prime is 28087373. The next prime is 28087429. The reversal of 28087380 is 8378082.

It can be written as a sum of positive squares in 2 ways, for example, as 22240656 + 5846724 = 4716^2 + 2418^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 77841 + ... + 78200.

It is an arithmetic number, because the mean of its divisors is an integer number (2366637).

Almost surely, 2^28087380 is an apocalyptic number.

28087380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28087380 is an abundant number, since it is smaller than the sum of its proper divisors (57111552).

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

28087380 is a wasteful number, since it uses less digits than its factorization.

28087380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156056 (or 156051 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 28087380 is about 5299.7528244249. The cubic root of 28087380 is about 303.9744467210.

The spelling of 28087380 in words is "twenty-eight million, eighty-seven thousand, three hundred eighty".