28745666 has 4 divisors (see below), whose sum is σ = 43118502. Its totient is φ = 14372832.

The previous prime is 28745627. The next prime is 28745669. The reversal of 28745666 is 66654782.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 21298225 + 7447441 = 4615^2 + 2729^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28745669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7186415 + ... + 7186418.

Almost surely, 2^28745666 is an apocalyptic number.

28745666 is a deficient number, since it is larger than the sum of its proper divisors (14372836).

28745666 is a wasteful number, since it uses less digits than its factorization.

28745666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14372835.

The product of its digits is 483840, while the sum is 44.

The square root of 28745666 is about 5361.4984845657. The cubic root of 28745666 is about 306.3308893091.

The spelling of 28745666 in words is "twenty-eight million, seven hundred forty-five thousand, six hundred sixty-six".