28739689 has 4 divisors (see below), whose sum is σ = 31352400. Its totient is φ = 26126980.

The previous prime is 28739681. The next prime is 28739693. The reversal of 28739689 is 98693782.

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 28739689 - 2³ = 28739681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28739681) 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, 1306339 + ... + 1306360.

It is an arithmetic number, because the mean of its divisors is an integer number (7838100).

Almost surely, 2^28739689 is an apocalyptic number.

It is an amenable number.

28739689 is a deficient number, since it is larger than the sum of its proper divisors (2612711).

28739689 is a wasteful number, since it uses less digits than its factorization.

28739689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2612710.

The product of its digits is 1306368, while the sum is 52.

The square root of 28739689 is about 5360.9410554491. The cubic root of 28739689 is about 306.3096563501.

The spelling of 28739689 in words is "twenty-eight million, seven hundred thirty-nine thousand, six hundred eighty-nine".