28767789 has 6 divisors (see below), whose sum is σ = 41553486. Its totient is φ = 19178520.

The previous prime is 28767787. The next prime is 28767821. The reversal of 28767789 is 98776782.

It can be written as a sum of positive squares in only one way, i.e., 28355625 + 412164 = 5325^2 + 642^2 .

It is not a de Polignac number, because 28767789 - 2¹ = 28767787 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28767787) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1598202 + ... + 1598219.

It is an arithmetic number, because the mean of its divisors is an integer number (6925581).

Almost surely, 2^28767789 is an apocalyptic number.

It is an amenable number.

28767789 is a deficient number, since it is larger than the sum of its proper divisors (12785697).

28767789 is a wasteful number, since it uses less digits than its factorization.

28767789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3196427 (or 3196424 counting only the distinct ones).

The product of its digits is 2370816, while the sum is 54.

The square root of 28767789 is about 5363.5612236647. The cubic root of 28767789 is about 306.4094544333.

The spelling of 28767789 in words is "twenty-eight million, seven hundred sixty-seven thousand, seven hundred eighty-nine".