20657173 has 2 divisors, whose sum is σ = 20657174. Its totient is φ = 20657172.

The previous prime is 20657171. The next prime is 20657179. The reversal of 20657173 is 37175602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12687844 + 7969329 = 3562^2 + 2823^2 .

It is a cyclic number.

It is not a de Polignac number, because 20657173 - 2¹ = 20657171 is a prime.

Together with 20657171, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20657171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10328586 + 10328587.

It is an arithmetic number, because the mean of its divisors is an integer number (10328587).

Almost surely, 2^20657173 is an apocalyptic number.

It is an amenable number.

20657173 is a deficient number, since it is larger than the sum of its proper divisors (1).

20657173 is an equidigital number, since it uses as much as digits as its factorization.

20657173 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8820, while the sum is 31.

The square root of 20657173 is about 4545.0162815990. The cubic root of 20657173 is about 274.3828496465.

The spelling of 20657173 in words is "twenty million, six hundred fifty-seven thousand, one hundred seventy-three".