28661181 has 8 divisors (see below), whose sum is σ = 38936160. Its totient is φ = 18746832.

The previous prime is 28661179. The next prime is 28661183. The reversal of 28661181 is 18116682.

It is an interprime number because it is at equal distance from previous prime (28661179) and next prime (28661183).

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

It is not a de Polignac number, because 28661181 - 2¹ = 28661179 is a prime.

It is a super-2 number, since 2×28661181² = 1642926592629522, which contains 22 as substring.

It is a congruent 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, 89971 + ... + 90288.

It is an arithmetic number, because the mean of its divisors is an integer number (4867020).

Almost surely, 2^28661181 is an apocalyptic number.

It is an amenable number.

28661181 is a deficient number, since it is larger than the sum of its proper divisors (10274979).

28661181 is a wasteful number, since it uses less digits than its factorization.

28661181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180315.

The product of its digits is 4608, while the sum is 33.

The square root of 28661181 is about 5353.6138261925. The cubic root of 28661181 is about 306.0304873721.

The spelling of 28661181 in words is "twenty-eight million, six hundred sixty-one thousand, one hundred eighty-one".