197157989 has 8 divisors (see below), whose sum is σ = 225446208. Its totient is φ = 168900480.

The previous prime is 197157977. The next prime is 197158007. The reversal of 197157989 is 989751791.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 197157989 - 2²⁰ = 196109413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (197157949) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8309 + ... + 21525.

It is an arithmetic number, because the mean of its divisors is an integer number (28180776).

Almost surely, 2^197157989 is an apocalyptic number.

It is an amenable number.

197157989 is a deficient number, since it is larger than the sum of its proper divisors (28288219).

197157989 is a wasteful number, since it uses less digits than its factorization.

197157989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15355.

The product of its digits is 1428840, while the sum is 56.

The square root of 197157989 is about 14041.2958447573. The cubic root of 197157989 is about 582.0202921169.

The spelling of 197157989 in words is "one hundred ninety-seven million, one hundred fifty-seven thousand, nine hundred eighty-nine".