28243917 has 32 divisors (see below), whose sum is σ = 45772160. Its totient is φ = 17107200.

The previous prime is 28243909. The next prime is 28243921. The reversal of 28243917 is 71934282.

It is not a de Polignac number, because 28243917 - 2³ = 28243909 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 (28243907) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22917 + ... + 24117.

It is an arithmetic number, because the mean of its divisors is an integer number (1430380).

Almost surely, 2^28243917 is an apocalyptic number.

28243917 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

28243917 is a deficient number, since it is larger than the sum of its proper divisors (17528243).

28243917 is a wasteful number, since it uses less digits than its factorization.

28243917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1290 (or 1284 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 28243917 is about 5314.5006350550. The cubic root of 28243917 is about 304.5381058381.

The spelling of 28243917 in words is "twenty-eight million, two hundred forty-three thousand, nine hundred seventeen".