20505713 has 2 divisors, whose sum is σ = 20505714. Its totient is φ = 20505712.

The previous prime is 20505707. The next prime is 20505761. The reversal of 20505713 is 31750502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13890529 + 6615184 = 3727^2 + 2572^2 .

It is a cyclic number.

It is not a de Polignac number, because 20505713 - 2¹⁶ = 20440177 is a prime.

It is not a weakly prime, because it can be changed into another prime (20504713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10252856 + 10252857.

It is an arithmetic number, because the mean of its divisors is an integer number (10252857).

Almost surely, 2^20505713 is an apocalyptic number.

It is an amenable number.

20505713 is a deficient number, since it is larger than the sum of its proper divisors (1).

20505713 is an equidigital number, since it uses as much as digits as its factorization.

20505713 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1050, while the sum is 23.

The square root of 20505713 is about 4528.3234204284. The cubic root of 20505713 is about 273.7106051746.

The spelling of 20505713 in words is "twenty million, five hundred five thousand, seven hundred thirteen".