20741729 has 2 divisors, whose sum is σ = 20741730. Its totient is φ = 20741728.

The previous prime is 20741723. The next prime is 20741731. The reversal of 20741729 is 92714702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20720704 + 21025 = 4552^2 + 145^2 .

It is a cyclic number.

It is not a de Polignac number, because 20741729 - 2⁴ = 20741713 is a prime.

Together with 20741731, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20741695 and 20741704.

It is not a weakly prime, because it can be changed into another prime (20741723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10370864 + 10370865.

It is an arithmetic number, because the mean of its divisors is an integer number (10370865).

Almost surely, 2^20741729 is an apocalyptic number.

It is an amenable number.

20741729 is a deficient number, since it is larger than the sum of its proper divisors (1).

20741729 is an equidigital number, since it uses as much as digits as its factorization.

20741729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7056, while the sum is 32.

The square root of 20741729 is about 4554.3088388909. The cubic root of 20741729 is about 274.7567170709.

The spelling of 20741729 in words is "twenty million, seven hundred forty-one thousand, seven hundred twenty-nine".