20803729 has 2 divisors, whose sum is σ = 20803730. Its totient is φ = 20803728.

The previous prime is 20803709. The next prime is 20803777. The reversal of 20803729 is 92730802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15421329 + 5382400 = 3927^2 + 2320^2 .

It is a cyclic number.

It is not a de Polignac number, because 20803729 - 2⁹ = 20803217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20803729.

It is not a weakly prime, because it can be changed into another prime (20803709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10401864 + 10401865.

It is an arithmetic number, because the mean of its divisors is an integer number (10401865).

Almost surely, 2^20803729 is an apocalyptic number.

It is an amenable number.

20803729 is a deficient number, since it is larger than the sum of its proper divisors (1).

20803729 is an equidigital number, since it uses as much as digits as its factorization.

20803729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 20803729 is about 4561.1105007443. The cubic root of 20803729 is about 275.0302071501.

The spelling of 20803729 in words is "twenty million, eight hundred three thousand, seven hundred twenty-nine".