28661818 has 16 divisors (see below), whose sum is σ = 45089856. Its totient is φ = 13638240.

The previous prime is 28661807. The next prime is 28661819. The reversal of 28661818 is 81816682.

It is a super-2 number, since 2×28661818² = 1642999622130248, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28661819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8230 + ... + 11182.

It is an arithmetic number, because the mean of its divisors is an integer number (2818116).

Almost surely, 2^28661818 is an apocalyptic number.

28661818 is a deficient number, since it is larger than the sum of its proper divisors (16428038).

28661818 is a wasteful number, since it uses less digits than its factorization.

28661818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3189.

The product of its digits is 36864, while the sum is 40.

The square root of 28661818 is about 5353.6733183862. The cubic root of 28661818 is about 306.0327545498.

The spelling of 28661818 in words is "twenty-eight million, six hundred sixty-one thousand, eight hundred eighteen".