28331998 has 16 divisors (see below), whose sum is σ = 45186336. Its totient is φ = 13293280.

The previous prime is 28331987. The next prime is 28332001. The reversal of 28331998 is 89913382.

It is a happy number.

It is a super-2 number, since 2×28331998² = 1605404221344008, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3373 + ... + 8248.

It is an arithmetic number, because the mean of its divisors is an integer number (2824146).

Almost surely, 2^28331998 is an apocalyptic number.

28331998 is a deficient number, since it is larger than the sum of its proper divisors (16854338).

28331998 is a wasteful number, since it uses less digits than its factorization.

28331998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11699.

The product of its digits is 93312, while the sum is 43.

The square root of 28331998 is about 5322.7810400203. The cubic root of 28331998 is about 304.8543531064.

The spelling of 28331998 in words is "twenty-eight million, three hundred thirty-one thousand, nine hundred ninety-eight".