195437889649 has 4 divisors (see below), whose sum is σ = 195439765360. Its totient is φ = 195436013940.

The previous prime is 195437889611. The next prime is 195437889679. The reversal of 195437889649 is 946988734591.

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: 946988734591 = 523 ⋅1810685917.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-195437889649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (195437889679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 771759 + ... + 993220.

It is an arithmetic number, because the mean of its divisors is an integer number (48859941340).

Almost surely, 2^195437889649 is an apocalyptic number.

It is an amenable number.

195437889649 is a deficient number, since it is larger than the sum of its proper divisors (1875711).

195437889649 is a wasteful number, since it uses less digits than its factorization.

195437889649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1875710.

The product of its digits is 470292480, while the sum is 73.

The spelling of 195437889649 in words is "one hundred ninety-five billion, four hundred thirty-seven million, eight hundred eighty-nine thousand, six hundred forty-nine".