197796721 has 2 divisors, whose sum is σ = 197796722. Its totient is φ = 197796720.

The previous prime is 197796713. The next prime is 197796787. The reversal of 197796721 is 127697791.

197796721 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., 197796096 + 625 = 14064^2 + 25^2 .

It is a cyclic number.

It is not a de Polignac number, because 197796721 - 2³ = 197796713 is a prime.

It is not a weakly prime, because it can be changed into another prime (197796121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98898360 + 98898361.

It is an arithmetic number, because the mean of its divisors is an integer number (98898361).

Almost surely, 2^197796721 is an apocalyptic number.

It is an amenable number.

197796721 is a deficient number, since it is larger than the sum of its proper divisors (1).

197796721 is an equidigital number, since it uses as much as digits as its factorization.

197796721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 333396, while the sum is 49.

The square root of 197796721 is about 14064.0222198346. The cubic root of 197796721 is about 582.6481375830.

The spelling of 197796721 in words is "one hundred ninety-seven million, seven hundred ninety-six thousand, seven hundred twenty-one".