197395921 has 4 divisors (see below), whose sum is σ = 207785200. Its totient is φ = 187006644.

The previous prime is 197395901. The next prime is 197395937. The reversal of 197395921 is 129593791.

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, and also an emirpimes, since its reverse is a distinct semiprime: 129593791 = 1277 ⋅101483.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-197395921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (197395901) 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, 5194611 + ... + 5194648.

It is an arithmetic number, because the mean of its divisors is an integer number (51946300).

Almost surely, 2^197395921 is an apocalyptic number.

It is an amenable number.

197395921 is a deficient number, since it is larger than the sum of its proper divisors (10389279).

197395921 is a wasteful number, since it uses less digits than its factorization.

197395921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10389278.

The product of its digits is 153090, while the sum is 46.

The square root of 197395921 is about 14049.7658699353. The cubic root of 197395921 is about 582.2543270709.

The spelling of 197395921 in words is "one hundred ninety-seven million, three hundred ninety-five thousand, nine hundred twenty-one".