28220564 has 6 divisors (see below), whose sum is σ = 49385994. Its totient is φ = 14110280.

The previous prime is 28220551. The next prime is 28220579. The reversal of 28220564 is 46502282.

It can be written as a sum of positive squares in only one way, i.e., 26419600 + 1800964 = 5140^2 + 1342^2 .

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 3527567 + ... + 3527574.

It is an arithmetic number, because the mean of its divisors is an integer number (8230999).

Almost surely, 2^28220564 is an apocalyptic number.

It is an amenable number.

28220564 is a deficient number, since it is larger than the sum of its proper divisors (21165430).

28220564 is a wasteful number, since it uses less digits than its factorization.

28220564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7055145 (or 7055143 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 29.

The square root of 28220564 is about 5312.3030787032. The cubic root of 28220564 is about 304.4541486518.

The spelling of 28220564 in words is "twenty-eight million, two hundred twenty thousand, five hundred sixty-four".