197664749 has 4 divisors (see below), whose sum is σ = 200046336. Its totient is φ = 195283164.

The previous prime is 197664743. The next prime is 197664787. The reversal of 197664749 is 947466791.

It is a happy number.

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 197664749 - 2²⁴ = 180887533 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 197664749.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (197664743) 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 3 ways as a sum of consecutive naturals, for example, 1190669 + ... + 1190834.

It is an arithmetic number, because the mean of its divisors is an integer number (50011584).

Almost surely, 2^197664749 is an apocalyptic number.

It is an amenable number.

197664749 is a deficient number, since it is larger than the sum of its proper divisors (2381587).

197664749 is an equidigital number, since it uses as much as digits as its factorization.

197664749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2381586.

The product of its digits is 2286144, while the sum is 53.

The square root of 197664749 is about 14059.3296070616. The cubic root of 197664749 is about 582.5185258158.

The spelling of 197664749 in words is "one hundred ninety-seven million, six hundred sixty-four thousand, seven hundred forty-nine".