197821361 has 2 divisors, whose sum is σ = 197821362. Its totient is φ = 197821360.

The previous prime is 197821357. The next prime is 197821373. The reversal of 197821361 is 163128791.

197821361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 186049600 + 11771761 = 13640^2 + 3431^2 .

It is a cyclic number.

It is not a de Polignac number, because 197821361 - 2² = 197821357 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (197821301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98910680 + 98910681.

It is an arithmetic number, because the mean of its divisors is an integer number (98910681).

Almost surely, 2^197821361 is an apocalyptic number.

It is an amenable number.

197821361 is a deficient number, since it is larger than the sum of its proper divisors (1).

197821361 is an equidigital number, since it uses as much as digits as its factorization.

197821361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 38.

The square root of 197821361 is about 14064.8981866205. The cubic root of 197821361 is about 582.6723305254.

The spelling of 197821361 in words is "one hundred ninety-seven million, eight hundred twenty-one thousand, three hundred sixty-one".