20729713 has 2 divisors, whose sum is σ = 20729714. Its totient is φ = 20729712.

The previous prime is 20729711. The next prime is 20729743. The reversal of 20729713 is 31792702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18258529 + 2471184 = 4273^2 + 1572^2 .

It is a cyclic number.

It is not a de Polignac number, because 20729713 - 2¹ = 20729711 is a prime.

Together with 20729711, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20729711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10364856 + 10364857.

It is an arithmetic number, because the mean of its divisors is an integer number (10364857).

Almost surely, 2^20729713 is an apocalyptic number.

It is an amenable number.

20729713 is a deficient number, since it is larger than the sum of its proper divisors (1).

20729713 is an equidigital number, since it uses as much as digits as its factorization.

20729713 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5292, while the sum is 31.

The square root of 20729713 is about 4552.9894574883. The cubic root of 20729713 is about 274.7036499030.

The spelling of 20729713 in words is "twenty million, seven hundred twenty-nine thousand, seven hundred thirteen".