28728337 has 4 divisors (see below), whose sum is σ = 31340016. Its totient is φ = 26116660.

The previous prime is 28728319. The next prime is 28728341. The reversal of 28728337 is 73382782.

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 a cyclic number.

It is not a de Polignac number, because 28728337 - 2²³ = 20339729 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 28728337.

It is not an unprimeable number, because it can be changed into a prime (28728307) 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, 1305823 + ... + 1305844.

It is an arithmetic number, because the mean of its divisors is an integer number (7835004).

Almost surely, 2^28728337 is an apocalyptic number.

It is an amenable number.

28728337 is a deficient number, since it is larger than the sum of its proper divisors (2611679).

28728337 is a wasteful number, since it uses less digits than its factorization.

28728337 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2611678.

The product of its digits is 112896, while the sum is 40.

The square root of 28728337 is about 5359.8821815409. The cubic root of 28728337 is about 306.2693208968.

The spelling of 28728337 in words is "twenty-eight million, seven hundred twenty-eight thousand, three hundred thirty-seven".