28984431 has 36 divisors (see below), whose sum is σ = 46811592. Its totient is φ = 15894144.

The previous prime is 28984409. The next prime is 28984433. The reversal of 28984431 is 13448982.

It is not a de Polignac number, because 28984431 - 2¹¹ = 28982383 is a prime.

It is a super-2 number, since 2×28984431² = 1680194480787522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28984431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28984433) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 397011 + ... + 397083.

It is an arithmetic number, because the mean of its divisors is an integer number (1300322).

Almost surely, 2^28984431 is an apocalyptic number.

28984431 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

28984431 is a deficient number, since it is larger than the sum of its proper divisors (17827161).

28984431 is an equidigital number, since it uses as much as digits as its factorization.

28984431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200 (or 120 counting only the distinct ones).

The product of its digits is 55296, while the sum is 39.

The square root of 28984431 is about 5383.7190677077. The cubic root of 28984431 is about 307.1766923811.

The spelling of 28984431 in words is "twenty-eight million, nine hundred eighty-four thousand, four hundred thirty-one".