28313399 has 4 divisors (see below), whose sum is σ = 29078664. Its totient is φ = 27548136.

The previous prime is 28313387. The next prime is 28313413. The reversal of 28313399 is 99331382.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99331382 = 2 ⋅49665691.

It is a cyclic number.

It is not a de Polignac number, because 28313399 - 2²⁰ = 27264823 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 (28313339) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 382577 + ... + 382650.

It is an arithmetic number, because the mean of its divisors is an integer number (7269666).

Almost surely, 2^28313399 is an apocalyptic number.

28313399 is a deficient number, since it is larger than the sum of its proper divisors (765265).

28313399 is an equidigital number, since it uses as much as digits as its factorization.

28313399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 765264.

The product of its digits is 34992, while the sum is 38.

The square root of 28313399 is about 5321.0336401868. The cubic root of 28313399 is about 304.7876296408.

The spelling of 28313399 in words is "twenty-eight million, three hundred thirteen thousand, three hundred ninety-nine".