28645820 has 24 divisors (see below), whose sum is σ = 68750304. Its totient is φ = 9821376.

The previous prime is 28645817. The next prime is 28645831. The reversal of 28645820 is 2854682.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 102167 + ... + 102446.

It is an arithmetic number, because the mean of its divisors is an integer number (2864596).

Almost surely, 2^28645820 is an apocalyptic number.

28645820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28645820 is an abundant number, since it is smaller than the sum of its proper divisors (40104484).

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

28645820 is a wasteful number, since it uses less digits than its factorization.

28645820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204629 (or 204627 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 35.

The square root of 28645820 is about 5352.1789955120. The cubic root of 28645820 is about 305.9758051128.

The spelling of 28645820 in words is "twenty-eight million, six hundred forty-five thousand, eight hundred twenty".