197021 has 4 divisors (see below), whose sum is σ = 214944. Its totient is φ = 179100.

The previous prime is 197009. The next prime is 197023. The reversal of 197021 is 120791.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 197021 - 2¹⁰ = 195997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 196984 and 197002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (197023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8945 + ... + 8966.

It is an arithmetic number, because the mean of its divisors is an integer number (53736).

2¹⁹⁷⁰²¹ is an apocalyptic number.

197021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

197021 is a deficient number, since it is larger than the sum of its proper divisors (17923).

197021 is a wasteful number, since it uses less digits than its factorization.

197021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17922.

The product of its (nonzero) digits is 126, while the sum is 20.

The square root of 197021 is about 443.8704766033. The cubic root of 197021 is about 58.1885461414.

It can be divided in two parts, 1970 and 21, that added together give a palindrome (1991).

The spelling of 197021 in words is "one hundred ninety-seven thousand, twenty-one".