28131129 has 12 divisors (see below), whose sum is σ = 43759716. Its totient is φ = 17311392.

The previous prime is 28131121. The next prime is 28131133. The reversal of 28131129 is 92113182.

It can be written as a sum of positive squares in 2 ways, for example, as 1505529 + 26625600 = 1227^2 + 5160^2 .

It is not a de Polignac number, because 28131129 - 2³ = 28131121 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28131121) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 120102 + ... + 120335.

It is an arithmetic number, because the mean of its divisors is an integer number (3646643).

Almost surely, 2^28131129 is an apocalyptic number.

It is an amenable number.

28131129 is a deficient number, since it is larger than the sum of its proper divisors (15628587).

28131129 is a wasteful number, since it uses less digits than its factorization.

28131129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240456 (or 240453 counting only the distinct ones).

The product of its digits is 864, while the sum is 27.

The square root of 28131129 is about 5303.8786750830. The cubic root of 28131129 is about 304.1321887319.

The spelling of 28131129 in words is "twenty-eight million, one hundred thirty-one thousand, one hundred twenty-nine".