28689660 has 48 divisors (see below), whose sum is σ = 89258400. Its totient is φ = 7650432.

The previous prime is 28689649. The next prime is 28689667. The reversal of 28689660 is 6698682.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28689667) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26025 + ... + 27104.

It is an arithmetic number, because the mean of its divisors is an integer number (1859550).

Almost surely, 2^28689660 is an apocalyptic number.

28689660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28689660 is an abundant number, since it is smaller than the sum of its proper divisors (60568740).

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

28689660 is a wasteful number, since it uses less digits than its factorization.

28689660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53147 (or 53139 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The square root of 28689660 is about 5356.2729579438. The cubic root of 28689660 is about 306.1318155665.

The spelling of 28689660 in words is "twenty-eight million, six hundred eighty-nine thousand, six hundred sixty".