28988091 has 48 divisors (see below), whose sum is σ = 49795200. Its totient is φ = 16608240.

The previous prime is 28988039. The next prime is 28988117. The reversal of 28988091 is 19088982.

It is not a de Polignac number, because 28988091 - 2⁷ = 28987963 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28988291) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 61840 + ... + 62306.

It is an arithmetic number, because the mean of its divisors is an integer number (1037400).

Almost surely, 2^28988091 is an apocalyptic number.

28988091 is a deficient number, since it is larger than the sum of its proper divisors (20807109).

28988091 is a wasteful number, since it uses less digits than its factorization.

28988091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 517 (or 500 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 45.

The square root of 28988091 is about 5384.0589707023. The cubic root of 28988091 is about 307.1896213840.

The spelling of 28988091 in words is "twenty-eight million, nine hundred eighty-eight thousand, ninety-one".