28815019 has 4 divisors (see below), whose sum is σ = 28974400. Its totient is φ = 28655640.

The previous prime is 28814969. The next prime is 28815029. The reversal of 28815019 is 91051882.

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-28815019 is a prime.

It is a super-2 number, since 2×28815019² = 1660610639940722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28815029) 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, 79419 + ... + 79780.

It is an arithmetic number, because the mean of its divisors is an integer number (7243600).

Almost surely, 2^28815019 is an apocalyptic number.

28815019 is a deficient number, since it is larger than the sum of its proper divisors (159381).

28815019 is a wasteful number, since it uses less digits than its factorization.

28815019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159380.

The product of its (nonzero) digits is 5760, while the sum is 34.

The square root of 28815019 is about 5367.9622763205. The cubic root of 28815019 is about 306.5770470375.

The spelling of 28815019 in words is "twenty-eight million, eight hundred fifteen thousand, nineteen".