28740511 has 4 divisors (see below), whose sum is σ = 28805832. Its totient is φ = 28675192.

The previous prime is 28740497. The next prime is 28740529. The reversal of 28740511 is 11504782.

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 28740511 - 2⁹ = 28739999 is a prime.

It is a super-2 number, since 2×28740511² = 1652033945082242, which contains 22 as substring.

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 28740511.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28740541) 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, 31996 + ... + 32881.

It is an arithmetic number, because the mean of its divisors is an integer number (7201458).

Almost surely, 2^28740511 is an apocalyptic number.

28740511 is a deficient number, since it is larger than the sum of its proper divisors (65321).

28740511 is an equidigital number, since it uses as much as digits as its factorization.

28740511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65320.

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 28740511 is about 5361.0177205452. The cubic root of 28740511 is about 306.3125766338.

The spelling of 28740511 in words is "twenty-eight million, seven hundred forty thousand, five hundred eleven".