28661187 has 8 divisors (see below), whose sum is σ = 38738704. Its totient is φ = 18845568.

The previous prime is 28661183. The next prime is 28661189. The reversal of 28661187 is 78116682.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28661187 - 2² = 28661183 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28661183) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65218 + ... + 65655.

It is an arithmetic number, because the mean of its divisors is an integer number (4842338).

Almost surely, 2^28661187 is an apocalyptic number.

28661187 is a deficient number, since it is larger than the sum of its proper divisors (10077517).

28661187 is a wasteful number, since it uses less digits than its factorization.

28661187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130949.

The product of its digits is 32256, while the sum is 39.

The square root of 28661187 is about 5353.6143865617. The cubic root of 28661187 is about 306.0305087271.

The spelling of 28661187 in words is "twenty-eight million, six hundred sixty-one thousand, one hundred eighty-seven".