196168386581 has 4 divisors (see below), whose sum is σ = 196169732652. Its totient is φ = 196167040512.

The previous prime is 196168386503. The next prime is 196168386593. The reversal of 196168386581 is 185683861691.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 147786424900 + 48381961681 = 384430^2 + 219959^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-196168386581 is a prime.

It is a super-2 number, since 2×196168386581² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (196168386181) 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, 423626 + ... + 756171.

It is an arithmetic number, because the mean of its divisors is an integer number (49042433163).

Almost surely, 2^196168386581 is an apocalyptic number.

It is an amenable number.

196168386581 is a deficient number, since it is larger than the sum of its proper divisors (1346071).

196168386581 is a wasteful number, since it uses less digits than its factorization.

196168386581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1346070.

The product of its digits is 14929920, while the sum is 62.

The spelling of 196168386581 in words is "one hundred ninety-six billion, one hundred sixty-eight million, three hundred eighty-six thousand, five hundred eighty-one".