28999191 has 16 divisors (see below), whose sum is σ = 41742176. Its totient is φ = 17801856.

The previous prime is 28999189. The next prime is 28999193. The reversal of 28999191 is 19199982.

It is an interprime number because it is at equal distance from previous prime (28999189) and next prime (28999193).

It is not a de Polignac number, because 28999191 - 2¹ = 28999189 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28999191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28999193) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23301 + ... + 24513.

It is an arithmetic number, because the mean of its divisors is an integer number (2608886).

Almost surely, 2^28999191 is an apocalyptic number.

28999191 is a deficient number, since it is larger than the sum of its proper divisors (12742985).

28999191 is a wasteful number, since it uses less digits than its factorization.

28999191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1842.

The product of its digits is 104976, while the sum is 48.

The square root of 28999191 is about 5385.0896928464. The cubic root of 28999191 is about 307.2288256405.

It can be divided in two parts, 2899 and 9191, that added together give a triangular number (12090 = T₁₅₅).

The spelling of 28999191 in words is "twenty-eight million, nine hundred ninety-nine thousand, one hundred ninety-one".