28517861 has 24 divisors (see below), whose sum is σ = 32277504. Its totient is φ = 25138080.

The previous prime is 28517851. The next prime is 28517893. The reversal of 28517861 is 16871582.

It is a de Polignac number, because none of the positive numbers 2^k-28517861 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28517821) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 606740 + ... + 606786.

It is an arithmetic number, because the mean of its divisors is an integer number (1344896).

Almost surely, 2^28517861 is an apocalyptic number.

It is an amenable number.

28517861 is a deficient number, since it is larger than the sum of its proper divisors (3759643).

28517861 is a wasteful number, since it uses less digits than its factorization.

28517861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161 (or 138 counting only the distinct ones).

The product of its digits is 26880, while the sum is 38.

The square root of 28517861 is about 5340.2116999235. The cubic root of 28517861 is about 305.5195337713.

The spelling of 28517861 in words is "twenty-eight million, five hundred seventeen thousand, eight hundred sixty-one".