28537668 has 18 divisors (see below), whose sum is σ = 72136974. Its totient is φ = 9512544.

The previous prime is 28537667. The next prime is 28537697. The reversal of 28537668 is 86673582.

It can be written as a sum of positive squares in only one way, i.e., 24920064 + 3617604 = 4992^2 + 1902^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (28537661) 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 5 ways as a sum of consecutive naturals, for example, 396321 + ... + 396392.

Almost surely, 2^28537668 is an apocalyptic number.

It is an amenable number.

28537668 is an abundant number, since it is smaller than the sum of its proper divisors (43599306).

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

28537668 is a wasteful number, since it uses less digits than its factorization.

28537668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 792723 (or 792718 counting only the distinct ones).

The product of its digits is 483840, while the sum is 45.

The square root of 28537668 is about 5342.0658925176. The cubic root of 28537668 is about 305.5902499790.

The spelling of 28537668 in words is "twenty-eight million, five hundred thirty-seven thousand, six hundred sixty-eight".