20490729 has 16 divisors (see below), whose sum is σ = 33061248. Its totient is φ = 11020032.

The previous prime is 20490727. The next prime is 20490749. The reversal of 20490729 is 92709402.

It is not a de Polignac number, because 20490729 - 2¹ = 20490727 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20490729.

It is not an unprimeable number, because it can be changed into a prime (20490727) 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 15 ways as a sum of consecutive naturals, for example, 28342 + ... + 29055.

It is an arithmetic number, because the mean of its divisors is an integer number (2066328).

Almost surely, 2^20490729 is an apocalyptic number.

It is an amenable number.

20490729 is a deficient number, since it is larger than the sum of its proper divisors (12570519).

20490729 is a wasteful number, since it uses less digits than its factorization.

20490729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57424.

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 20490729 is about 4526.6686426113. The cubic root of 20490729 is about 273.6439200337.

The spelling of 20490729 in words is "twenty million, four hundred ninety thousand, seven hundred twenty-nine".