20871743 has 2 divisors, whose sum is σ = 20871744. Its totient is φ = 20871742.

The previous prime is 20871731. The next prime is 20871757. The reversal of 20871743 is 34717802.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20871743 - 2¹⁶ = 20806207 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 (20871043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10435871 + 10435872.

It is an arithmetic number, because the mean of its divisors is an integer number (10435872).

Almost surely, 2^20871743 is an apocalyptic number.

20871743 is a deficient number, since it is larger than the sum of its proper divisors (1).

20871743 is an equidigital number, since it uses as much as digits as its factorization.

20871743 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 20871743 is about 4568.5602764985. The cubic root of 20871743 is about 275.3296014922.

The spelling of 20871743 in words is "twenty million, eight hundred seventy-one thousand, seven hundred forty-three".