28321816 has 32 divisors (see below), whose sum is σ = 55137600. Its totient is φ = 13628160.

The previous prime is 28321801. The next prime is 28321819. The reversal of 28321816 is 61812382.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28321819) 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, 25366 + ... + 26458.

It is an arithmetic number, because the mean of its divisors is an integer number (1723050).

Almost surely, 2^28321816 is an apocalyptic number.

It is an amenable number.

28321816 is a deficient number, since it is larger than the sum of its proper divisors (26815784).

28321816 is a wasteful number, since it uses less digits than its factorization.

28321816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1219 (or 1215 counting only the distinct ones).

The product of its digits is 4608, while the sum is 31.

The square root of 28321816 is about 5321.8244991732. The cubic root of 28321816 is about 304.8178290446.

The spelling of 28321816 in words is "twenty-eight million, three hundred twenty-one thousand, eight hundred sixteen".