28801387 has 4 divisors (see below), whose sum is σ = 29730496. Its totient is φ = 27872280.

The previous prime is 28801361. The next prime is 28801439. The reversal of 28801387 is 78310882.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28801387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28801307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 464508 + ... + 464569.

It is an arithmetic number, because the mean of its divisors is an integer number (7432624).

Almost surely, 2^28801387 is an apocalyptic number.

28801387 is a deficient number, since it is larger than the sum of its proper divisors (929109).

28801387 is an equidigital number, since it uses as much as digits as its factorization.

28801387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 929108.

The product of its (nonzero) digits is 21504, while the sum is 37.

The square root of 28801387 is about 5366.6923705389. The cubic root of 28801387 is about 306.5286935784.

The spelling of 28801387 in words is "twenty-eight million, eight hundred one thousand, three hundred eighty-seven".