28917109 has 8 divisors (see below), whose sum is σ = 31183712. Its totient is φ = 26656560.

The previous prime is 28917101. The next prime is 28917151. The reversal of 28917109 is 90171982.

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

It is a cyclic number.

It is not a de Polignac number, because 28917109 - 2³ = 28917101 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 (28917101) 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, 15922 + ... + 17644.

It is an arithmetic number, because the mean of its divisors is an integer number (3897964).

Almost surely, 2^28917109 is an apocalyptic number.

It is an amenable number.

28917109 is a deficient number, since it is larger than the sum of its proper divisors (2266603).

28917109 is a wasteful number, since it uses less digits than its factorization.

28917109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3027.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 28917109 is about 5377.4630635645. The cubic root of 28917109 is about 306.9386820634.

It can be divided in two parts, 2891 and 7109, that added together give a 4-th power (10000 = 10⁴).

The spelling of 28917109 in words is "twenty-eight million, nine hundred seventeen thousand, one hundred nine".