20713109 has 2 divisors, whose sum is σ = 20713110. Its totient is φ = 20713108.

The previous prime is 20713103. The next prime is 20713127. The reversal of 20713109 is 90131702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20702500 + 10609 = 4550^2 + 103^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20713109 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20713103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10356554 + 10356555.

It is an arithmetic number, because the mean of its divisors is an integer number (10356555).

Almost surely, 2^20713109 is an apocalyptic number.

It is an amenable number.

20713109 is a deficient number, since it is larger than the sum of its proper divisors (1).

20713109 is an equidigital number, since it uses as much as digits as its factorization.

20713109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 378, while the sum is 23.

The square root of 20713109 is about 4551.1656748574. The cubic root of 20713109 is about 274.6302866467.

The spelling of 20713109 in words is "twenty million, seven hundred thirteen thousand, one hundred nine".