166098221 has 2 divisors, whose sum is σ = 166098222. Its totient is φ = 166098220.

The previous prime is 166098187. The next prime is 166098223. The reversal of 166098221 is 122890661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 115132900 + 50965321 = 10730^2 + 7139^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166098221 is a prime.

It is a Sophie Germain prime.

Together with 166098223, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166098223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83049110 + 83049111.

It is an arithmetic number, because the mean of its divisors is an integer number (83049111).

Almost surely, 2^166098221 is an apocalyptic number.

It is an amenable number.

166098221 is a deficient number, since it is larger than the sum of its proper divisors (1).

166098221 is an equidigital number, since it uses as much as digits as its factorization.

166098221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 166098221 is about 12887.9098770902. The cubic root of 166098221 is about 549.6948400839.

The spelling of 166098221 in words is "one hundred sixty-six million, ninety-eight thousand, two hundred twenty-one".