28060991 has 4 divisors (see below), whose sum is σ = 32069712. Its totient is φ = 24052272.

The previous prime is 28060987. The next prime is 28060993. The reversal of 28060991 is 19906082.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28060991 - 2² = 28060987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28060993) 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, 2004350 + ... + 2004363.

It is an arithmetic number, because the mean of its divisors is an integer number (8017428).

Almost surely, 2^28060991 is an apocalyptic number.

28060991 is a deficient number, since it is larger than the sum of its proper divisors (4008721).

28060991 is an equidigital number, since it uses as much as digits as its factorization.

28060991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4008720.

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 28060991 is about 5297.2625949636. The cubic root of 28060991 is about 303.8792189572.

The spelling of 28060991 in words is "twenty-eight million, sixty thousand, nine hundred ninety-one".