28643769 has 24 divisors (see below), whose sum is σ = 51584832. Its totient is φ = 14879520.

The previous prime is 28643761. The next prime is 28643801. The reversal of 28643769 is 96734682.

It is not a de Polignac number, because 28643769 - 2³ = 28643761 is a prime.

It is a super-2 number, since 2×28643769² = 1640931005050722, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28643761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19974 + ... + 21359.

It is an arithmetic number, because the mean of its divisors is an integer number (2149368).

Almost surely, 2^28643769 is an apocalyptic number.

It is an amenable number.

28643769 is a deficient number, since it is larger than the sum of its proper divisors (22941063).

28643769 is a wasteful number, since it uses less digits than its factorization.

28643769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41357 (or 41354 counting only the distinct ones).

The product of its digits is 435456, while the sum is 45.

The square root of 28643769 is about 5351.9873878775. The cubic root of 28643769 is about 305.9685024609.

The spelling of 28643769 in words is "twenty-eight million, six hundred forty-three thousand, seven hundred sixty-nine".