28207789 has 4 divisors (see below), whose sum is σ = 28235680. Its totient is φ = 28179900.

The previous prime is 28207771. The next prime is 28207793. The reversal of 28207789 is 98770282.

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 28207789 - 2⁵ = 28207757 is a prime.

It is a super-3 number, since 3×28207789³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28207759) 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, 12369 + ... + 14470.

It is an arithmetic number, because the mean of its divisors is an integer number (7058920).

Almost surely, 2^28207789 is an apocalyptic number.

It is an amenable number.

28207789 is a deficient number, since it is larger than the sum of its proper divisors (27891).

28207789 is a wasteful number, since it uses less digits than its factorization.

28207789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27890.

The product of its (nonzero) digits is 112896, while the sum is 43.

The square root of 28207789 is about 5311.1005450848. The cubic root of 28207789 is about 304.4082012027.

It can be divided in two parts, 2820 and 7789, that added together give a square (10609 = 103²).

The spelling of 28207789 in words is "twenty-eight million, two hundred seven thousand, seven hundred eighty-nine".