28016989 has 24 divisors (see below), whose sum is σ = 37841472. Its totient is φ = 20142720.

The previous prime is 28016983. The next prime is 28016999. The reversal of 28016989 is 98961082.

It is a happy number.

It is not a de Polignac number, because 28016989 - 2⁵ = 28016957 is a prime.

It is a super-2 number, since 2×28016989² = 1569903345252242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28016983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11937 + ... + 14089.

It is an arithmetic number, because the mean of its divisors is an integer number (1576728).

Almost surely, 2^28016989 is an apocalyptic number.

It is an amenable number.

28016989 is a deficient number, since it is larger than the sum of its proper divisors (9824483).

28016989 is a wasteful number, since it uses less digits than its factorization.

28016989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2197 (or 2184 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 43.

The square root of 28016989 is about 5293.1076883056. The cubic root of 28016989 is about 303.7202997825.

The spelling of 28016989 in words is "twenty-eight million, sixteen thousand, nine hundred eighty-nine".