195018649421 has 12 divisors (see below), whose sum is σ = 198028712700. Its totient is φ = 192052680768.

The previous prime is 195018649409. The next prime is 195018649429. The reversal of 195018649421 is 124946810591.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 105372301321 + 89646348100 = 324611^2 + 299410^2 .

It is not a de Polignac number, because 195018649421 - 2²⁶ = 194951540557 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 195018649421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (195018649429) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2387585 + ... + 2467913.

It is an arithmetic number, because the mean of its divisors is an integer number (16502392725).

Almost surely, 2^195018649421 is an apocalyptic number.

It is an amenable number.

195018649421 is a deficient number, since it is larger than the sum of its proper divisors (3010063279).

195018649421 is an frugal number, since it uses more digits than its factorization.

195018649421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80876 (or 80797 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 50.

The spelling of 195018649421 in words is "one hundred ninety-five billion, eighteen million, six hundred forty-nine thousand, four hundred twenty-one".