2021208173 has 2 divisors, whose sum is σ = 2021208174. Its totient is φ = 2021208172.

The previous prime is 2021208143. The next prime is 2021208187. The reversal of 2021208173 is 3718021202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1601040169 + 420168004 = 40013^2 + 20498^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021208173 - 2¹² = 2021204077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2021208143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010604086 + 1010604087.

It is an arithmetic number, because the mean of its divisors is an integer number (1010604087).

Almost surely, 2^2021208173 is an apocalyptic number.

It is an amenable number.

2021208173 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021208173 is an equidigital number, since it uses as much as digits as its factorization.

2021208173 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 2021208173 is about 44957.8488475594. The cubic root of 2021208173 is about 1264.3588377010.

Adding to 2021208173 its reverse (3718021202), we get a palindrome (5739229375).

The spelling of 2021208173 in words is "two billion, twenty-one million, two hundred eight thousand, one hundred seventy-three".