28644129 has 12 divisors (see below), whose sum is σ = 41616276. Its totient is φ = 18984672.

The previous prime is 28644113. The next prime is 28644137. The reversal of 28644129 is 92144682.

28644129 is a `hidden beast` number, since 2 + 8 + 644 + 1 + 2 + 9 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 26010000 + 2634129 = 5100^2 + 1623^2 .

It is not a de Polignac number, because 28644129 - 2⁴ = 28644113 is a prime.

It is a super-2 number, since 2×28644129² = 1640972252337282, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28644093 and 28644102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28644829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7642 + ... + 10755.

It is an arithmetic number, because the mean of its divisors is an integer number (3468023).

Almost surely, 2^28644129 is an apocalyptic number.

It is an amenable number.

28644129 is a deficient number, since it is larger than the sum of its proper divisors (12972147).

28644129 is a wasteful number, since it uses less digits than its factorization.

28644129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18576 (or 18573 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 28644129 is about 5352.0210201381. The cubic root of 28644129 is about 305.9697842778.

It can be divided in two parts, 2864412 and 9, that added together give a triangular number (2864421 = T₂₃₉₃).

The spelling of 28644129 in words is "twenty-eight million, six hundred forty-four thousand, one hundred twenty-nine".