28972389 has 4 divisors (see below), whose sum is σ = 38629856. Its totient is φ = 19314924.

The previous prime is 28972379. The next prime is 28972417. The reversal of 28972389 is 98327982.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28972389 - 2¹⁷ = 28841317 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 (28972319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4828729 + ... + 4828734.

It is an arithmetic number, because the mean of its divisors is an integer number (9657464).

Almost surely, 2^28972389 is an apocalyptic number.

It is an amenable number.

28972389 is a deficient number, since it is larger than the sum of its proper divisors (9657467).

28972389 is an equidigital number, since it uses as much as digits as its factorization.

28972389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9657466.

The product of its digits is 435456, while the sum is 48.

The square root of 28972389 is about 5382.6005796455. The cubic root of 28972389 is about 307.1341461590.

The spelling of 28972389 in words is "twenty-eight million, nine hundred seventy-two thousand, three hundred eighty-nine".