197625737821 has 2 divisors, whose sum is σ = 197625737822. Its totient is φ = 197625737820.

The previous prime is 197625737819. The next prime is 197625737873. The reversal of 197625737821 is 128737526791.

197625737821 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., 165705984900 + 31919752921 = 407070^2 + 178661^2 .

It is an emirp because it is prime and its reverse (128737526791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 197625737821 - 2¹ = 197625737819 is a prime.

Together with 197625737819, 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 (197625537821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98812868910 + 98812868911.

It is an arithmetic number, because the mean of its divisors is an integer number (98812868911).

Almost surely, 2^197625737821 is an apocalyptic number.

It is an amenable number.

197625737821 is a deficient number, since it is larger than the sum of its proper divisors (1).

197625737821 is an equidigital number, since it uses as much as digits as its factorization.

197625737821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8890560, while the sum is 58.

The spelling of 197625737821 in words is "one hundred ninety-seven billion, six hundred twenty-five million, seven hundred thirty-seven thousand, eight hundred twenty-one".