28399516 has 12 divisors (see below), whose sum is σ = 49919688. Its totient is φ = 14136752.

The previous prime is 28399513. The next prime is 28399517. The reversal of 28399516 is 61599382.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28399513) 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, 14731 + ... + 16546.

It is an arithmetic number, because the mean of its divisors is an integer number (4159974).

Almost surely, 2^28399516 is an apocalyptic number.

It is an amenable number.

28399516 is a deficient number, since it is larger than the sum of its proper divisors (21520172).

28399516 is a wasteful number, since it uses less digits than its factorization.

28399516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31508 (or 31506 counting only the distinct ones).

The product of its digits is 116640, while the sum is 43.

The square root of 28399516 is about 5329.1196271054. The cubic root of 28399516 is about 305.0963271840.

It can be divided in two parts, 283 and 99516, that added together give a palindrome (99799).

The spelling of 28399516 in words is "twenty-eight million, three hundred ninety-nine thousand, five hundred sixteen".