28661895 has 12 divisors (see below), whose sum is σ = 49680696. Its totient is φ = 15286320.

The previous prime is 28661891. The next prime is 28661903. The reversal of 28661895 is 59816682.

28661895 is a `hidden beast` number, since 28 + 6 + 618 + 9 + 5 = 666.

It is not a de Polignac number, because 28661895 - 2² = 28661891 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 636931 = 28661895 / (2 + 8 + 6 + 6 + 1 + 8 + 9 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 28661895.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28661891) 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 11 ways as a sum of consecutive naturals, for example, 318421 + ... + 318510.

It is an arithmetic number, because the mean of its divisors is an integer number (4140058).

Almost surely, 2^28661895 is an apocalyptic number.

28661895 is a deficient number, since it is larger than the sum of its proper divisors (21018801).

28661895 is a wasteful number, since it uses less digits than its factorization.

28661895 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 636942 (or 636939 counting only the distinct ones).

The product of its digits is 207360, while the sum is 45.

The square root of 28661895 is about 5353.6805097054. The cubic root of 28661895 is about 306.0330286020.

It can be divided in two parts, 2866 and 1895, that added together give a square (4761 = 69²).

The spelling of 28661895 in words is "twenty-eight million, six hundred sixty-one thousand, eight hundred ninety-five".