28809613 has 8 divisors (see below), whose sum is σ = 33691328. Its totient is φ = 24119424.

The previous prime is 28809587. The next prime is 28809617. The reversal of 28809613 is 31690882.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-28809613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28809617) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47556 + ... + 48157.

It is an arithmetic number, because the mean of its divisors is an integer number (4211416).

Almost surely, 2^28809613 is an apocalyptic number.

It is an amenable number.

28809613 is a deficient number, since it is larger than the sum of its proper divisors (4881715).

28809613 is an equidigital number, since it uses as much as digits as its factorization.

28809613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95763.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 28809613 is about 5367.4587096689. The cubic root of 28809613 is about 306.5578734811.

The spelling of 28809613 in words is "twenty-eight million, eight hundred nine thousand, six hundred thirteen".