28773640 has 32 divisors (see below), whose sum is σ = 73990080. Its totient is φ = 9865152.

The previous prime is 28773637. The next prime is 28773649. The reversal of 28773640 is 4637782.

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 28773640.

It is not an unprimeable number, because it can be changed into a prime (28773649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51102 + ... + 51661.

It is an arithmetic number, because the mean of its divisors is an integer number (2312190).

Almost surely, 2^28773640 is an apocalyptic number.

28773640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28773640 is an abundant number, since it is smaller than the sum of its proper divisors (45216440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28773640 is a wasteful number, since it uses less digits than its factorization.

28773640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102781 (or 102777 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 37.

The square root of 28773640 is about 5364.1066357782. The cubic root of 28773640 is about 306.4302262786.

The spelling of 28773640 in words is "twenty-eight million, seven hundred seventy-three thousand, six hundred forty".