20947873 has 2 divisors, whose sum is σ = 20947874. Its totient is φ = 20947872.

The previous prime is 20947867. The next prime is 20947903. The reversal of 20947873 is 37874902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17909824 + 3038049 = 4232^2 + 1743^2 .

It is a cyclic number.

It is not a de Polignac number, because 20947873 - 2⁹ = 20947361 is a prime.

It is a plaindrome in base 13.

It is not a weakly prime, because it can be changed into another prime (20947573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10473936 + 10473937.

It is an arithmetic number, because the mean of its divisors is an integer number (10473937).

Almost surely, 2^20947873 is an apocalyptic number.

It is an amenable number.

20947873 is a deficient number, since it is larger than the sum of its proper divisors (1).

20947873 is an equidigital number, since it uses as much as digits as its factorization.

20947873 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84672, while the sum is 40.

The square root of 20947873 is about 4576.8846391405. The cubic root of 20947873 is about 275.6639516083.

The spelling of 20947873 in words is "twenty million, nine hundred forty-seven thousand, eight hundred seventy-three".