18612729 has 12 divisors (see below), whose sum is σ = 27541332. Its totient is φ = 12105600.

The previous prime is 18612709. The next prime is 18612743. The reversal of 18612729 is 92721681.

18612729 is a `hidden beast` number, since 18 + 612 + 7 + 29 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8037225 + 10575504 = 2835^2 + 3252^2 .

It is not a de Polignac number, because 18612729 - 2¹¹ = 18610681 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 18612693 and 18612702.

It is not an unprimeable number, because it can be changed into a prime (18612709) 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, 24852 + ... + 25589.

It is an arithmetic number, because the mean of its divisors is an integer number (2295111).

Almost surely, 2^18612729 is an apocalyptic number.

It is an amenable number.

18612729 is a deficient number, since it is larger than the sum of its proper divisors (8928603).

18612729 is a wasteful number, since it uses less digits than its factorization.

18612729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50488 (or 50485 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 18612729 is about 4314.2472112757. The cubic root of 18612729 is about 265.0147327753.

The spelling of 18612729 in words is "eighteen million, six hundred twelve thousand, seven hundred twenty-nine".