197979789 has 16 divisors (see below), whose sum is σ = 301991040. Its totient is φ = 113016000.

The previous prime is 197979787. The next prime is 197979797. The reversal of 197979789 is 987979791.

It is a happy number.

It is not a de Polignac number, because 197979789 - 2¹ = 197979787 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (197979787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19039 + ... + 27539.

It is an arithmetic number, because the mean of its divisors is an integer number (18874440).

Almost surely, 2^197979789 is an apocalyptic number.

It is an amenable number.

197979789 is a deficient number, since it is larger than the sum of its proper divisors (104011251).

197979789 is a wasteful number, since it uses less digits than its factorization.

197979789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9620.

The product of its digits is 18003384, while the sum is 66.

The square root of 197979789 is about 14070.5290945295. The cubic root of 197979789 is about 582.8278361112.

The spelling of 197979789 in words is "one hundred ninety-seven million, nine hundred seventy-nine thousand, seven hundred eighty-nine".