28651187 has 4 divisors (see below), whose sum is σ = 28670136. Its totient is φ = 28632240.

The previous prime is 28651157. The next prime is 28651199. The reversal of 28651187 is 78115682.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28651187 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28651187.

It is not an unprimeable number, because it can be changed into a prime (28651157) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6989 + ... + 10302.

It is an arithmetic number, because the mean of its divisors is an integer number (7167534).

Almost surely, 2^28651187 is an apocalyptic number.

28651187 is a deficient number, since it is larger than the sum of its proper divisors (18949).

28651187 is a wasteful number, since it uses less digits than its factorization.

28651187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18948.

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

The square root of 28651187 is about 5352.6803566064. The cubic root of 28651187 is about 305.9949128407.

The spelling of 28651187 in words is "twenty-eight million, six hundred fifty-one thousand, one hundred eighty-seven".