28970091 has 12 divisors (see below), whose sum is σ = 44307432. Its totient is φ = 18177216.

The previous prime is 28970083. The next prime is 28970093. The reversal of 28970091 is 19007982.

It is a happy number.

It is not a de Polignac number, because 28970091 - 2³ = 28970083 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28970093) 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 11 ways as a sum of consecutive naturals, for example, 94521 + ... + 94826.

It is an arithmetic number, because the mean of its divisors is an integer number (3692286).

Almost surely, 2^28970091 is an apocalyptic number.

28970091 is a deficient number, since it is larger than the sum of its proper divisors (15337341).

28970091 is a wasteful number, since it uses less digits than its factorization.

28970091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189370 (or 189367 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 28970091 is about 5382.3871098240. The cubic root of 28970091 is about 307.1260256351.

The spelling of 28970091 in words is "twenty-eight million, nine hundred seventy thousand, ninety-one".