28989739 has 4 divisors (see below), whose sum is σ = 29024424. Its totient is φ = 28955056.

The previous prime is 28989731. The next prime is 28989757. The reversal of 28989739 is 93798982.

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 28989739 - 2³ = 28989731 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28989739.

It is not an unprimeable number, because it can be changed into a prime (28989731) 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, 16057 + ... + 17770.

It is an arithmetic number, because the mean of its divisors is an integer number (7256106).

Almost surely, 2^28989739 is an apocalyptic number.

28989739 is a deficient number, since it is larger than the sum of its proper divisors (34685).

28989739 is an equidigital number, since it uses as much as digits as its factorization.

28989739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34684.

The product of its digits is 1959552, while the sum is 55.

The square root of 28989739 is about 5384.2120129133. The cubic root of 28989739 is about 307.1954426125.

It can be divided in two parts, 2898973 and 9, that added together give a palindrome (2898982).

The spelling of 28989739 in words is "twenty-eight million, nine hundred eighty-nine thousand, seven hundred thirty-nine".