197821373 has 2 divisors, whose sum is σ = 197821374. Its totient is φ = 197821372.

The previous prime is 197821361. The next prime is 197821391. The reversal of 197821373 is 373128791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 177768889 + 20052484 = 13333^2 + 4478^2 .

It is a cyclic number.

It is not a de Polignac number, because 197821373 - 2⁴ = 197821357 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 197821373.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197821343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98910686 + 98910687.

It is an arithmetic number, because the mean of its divisors is an integer number (98910687).

Almost surely, 2^197821373 is an apocalyptic number.

It is an amenable number.

197821373 is a deficient number, since it is larger than the sum of its proper divisors (1).

197821373 is an equidigital number, since it uses as much as digits as its factorization.

197821373 is an evil number, because the sum of its binary digits is even.

The product of its digits is 63504, while the sum is 41.

The square root of 197821373 is about 14064.8986132144. The cubic root of 197821373 is about 582.6723423071.

The spelling of 197821373 in words is "one hundred ninety-seven million, eight hundred twenty-one thousand, three hundred seventy-three".