28913917 has 8 divisors (see below), whose sum is σ = 30294272. Its totient is φ = 27561600.

The previous prime is 28913903. The next prime is 28913947. The reversal of 28913917 is 71931982.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28913917 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28913917.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28913947) 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, 4884 + ... + 9037.

It is an arithmetic number, because the mean of its divisors is an integer number (3786784).

Almost surely, 2^28913917 is an apocalyptic number.

It is an amenable number.

28913917 is a deficient number, since it is larger than the sum of its proper divisors (1380355).

28913917 is a wasteful number, since it uses less digits than its factorization.

28913917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14019.

The product of its digits is 27216, while the sum is 40.

The square root of 28913917 is about 5377.1662611454. The cubic root of 28913917 is about 306.9273878923.

The spelling of 28913917 in words is "twenty-eight million, nine hundred thirteen thousand, nine hundred seventeen".