28993317 has 8 divisors (see below), whose sum is σ = 40338624. Its totient is φ = 18488448.

The previous prime is 28993303. The next prime is 28993319. The reversal of 28993317 is 71339982.

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

It is not a de Polignac number, because 28993317 - 2⁷ = 28993189 is a prime.

It is a super-2 number, since 2×28993317² = 1681224861324978, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28993319) 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, 210028 + ... + 210165.

It is an arithmetic number, because the mean of its divisors is an integer number (5042328).

Almost surely, 2^28993317 is an apocalyptic number.

It is an amenable number.

28993317 is a deficient number, since it is larger than the sum of its proper divisors (11345307).

28993317 is a wasteful number, since it uses less digits than its factorization.

28993317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420219.

The product of its digits is 81648, while the sum is 42.

The square root of 28993317 is about 5384.5442704095. The cubic root of 28993317 is about 307.2080804183.

It can be divided in two parts, 2899 and 3317, that added together give a triangular number (6216 = T₁₁₁).

The spelling of 28993317 in words is "twenty-eight million, nine hundred ninety-three thousand, three hundred seventeen".