197621 has 2 divisors, whose sum is σ = 197622. Its totient is φ = 197620.

The previous prime is 197609. The next prime is 197641. The reversal of 197621 is 126791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 192721 + 4900 = 439^2 + 70^2 .

It is a cyclic number.

It is not a de Polignac number, because 197621 - 2¹⁰ = 196597 is a prime.

It is a Sophie Germain prime.

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 (197641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98810 + 98811.

It is an arithmetic number, because the mean of its divisors is an integer number (98811).

2¹⁹⁷⁶²¹ is an apocalyptic number.

It is an amenable number.

197621 is a deficient number, since it is larger than the sum of its proper divisors (1).

197621 is an equidigital number, since it uses as much as digits as its factorization.

197621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 756, while the sum is 26.

The square root of 197621 is about 444.5458356570. The cubic root of 197621 is about 58.2475546506.

It can be divided in two parts, 197 and 621, that added together give a palindrome (818).

The spelling of 197621 in words is "one hundred ninety-seven thousand, six hundred twenty-one".