28583991 has 12 divisors (see below), whose sum is σ = 41340520. Its totient is φ = 19031760.

The previous prime is 28583983. The next prime is 28583993. The reversal of 28583991 is 19938582.

It is a happy number.

It is not a de Polignac number, because 28583991 - 2³ = 28583983 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 (28583993) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8136 + ... + 11106.

Almost surely, 2^28583991 is an apocalyptic number.

28583991 is a deficient number, since it is larger than the sum of its proper divisors (12756529).

28583991 is a wasteful number, since it uses less digits than its factorization.

28583991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4046 (or 4043 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The square root of 28583991 is about 5346.3998166991. The cubic root of 28583991 is about 305.7555076387.

The spelling of 28583991 in words is "twenty-eight million, five hundred eighty-three thousand, nine hundred ninety-one".