20871973 has 2 divisors, whose sum is σ = 20871974. Its totient is φ = 20871972.

The previous prime is 20871923. The next prime is 20872003. The reversal of 20871973 is 37917802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14884164 + 5987809 = 3858^2 + 2447^2 .

It is a cyclic number.

It is not a de Polignac number, because 20871973 - 2¹³ = 20863781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20871923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10435986 + 10435987.

It is an arithmetic number, because the mean of its divisors is an integer number (10435987).

Almost surely, 2^20871973 is an apocalyptic number.

It is an amenable number.

20871973 is a deficient number, since it is larger than the sum of its proper divisors (1).

20871973 is an equidigital number, since it uses as much as digits as its factorization.

20871973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 20871973 is about 4568.5854484731. The cubic root of 20871973 is about 275.3306128369.

The spelling of 20871973 in words is "twenty million, eight hundred seventy-one thousand, nine hundred seventy-three".