28996291 has 4 divisors (see below), whose sum is σ = 29012872. Its totient is φ = 28979712.

The previous prime is 28996249. The next prime is 28996309. The reversal of 28996291 is 19269982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19269982 = 2 ⋅9634991.

It is a cyclic number.

It is not a de Polignac number, because 28996291 - 2¹¹ = 28994243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28996211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5310 + ... + 9283.

It is an arithmetic number, because the mean of its divisors is an integer number (7253218).

Almost surely, 2^28996291 is an apocalyptic number.

28996291 is a deficient number, since it is larger than the sum of its proper divisors (16581).

28996291 is a wasteful number, since it uses less digits than its factorization.

28996291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16580.

The product of its digits is 139968, while the sum is 46.

The square root of 28996291 is about 5384.8204241182. The cubic root of 28996291 is about 307.2185840526.

It can be divided in two parts, 289 and 96291, that added together give a triangular number (96580 = T₄₃₉).

The spelling of 28996291 in words is "twenty-eight million, nine hundred ninety-six thousand, two hundred ninety-one".