197991743 has 4 divisors (see below), whose sum is σ = 198107208. Its totient is φ = 197876280.

The previous prime is 197991733. The next prime is 197991763. The reversal of 197991743 is 347199791.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 347199791 = 6199 ⋅56009.

It is a cyclic number.

It is not a de Polignac number, because 197991743 - 2²⁶ = 130882879 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 197991691 and 197991700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (197991713) 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, 55121 + ... + 58602.

It is an arithmetic number, because the mean of its divisors is an integer number (49526802).

Almost surely, 2^197991743 is an apocalyptic number.

197991743 is a deficient number, since it is larger than the sum of its proper divisors (115465).

197991743 is a wasteful number, since it uses less digits than its factorization.

197991743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115464.

The product of its digits is 428652, while the sum is 50.

The square root of 197991743 is about 14070.9538766922. The cubic root of 197991743 is about 582.8395662374.

The spelling of 197991743 in words is "one hundred ninety-seven million, nine hundred ninety-one thousand, seven hundred forty-three".