196823815391 has 24 divisors (see below), whose sum is σ = 234114102720. Its totient is φ = 164915860032.

The previous prime is 196823815373. The next prime is 196823815459. The reversal of 196823815391 is 193518328691.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-196823815391 is a prime.

It is a super-2 number, since 2×196823815391² (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 (196823815351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1857641 + ... + 1960733.

It is an arithmetic number, because the mean of its divisors is an integer number (9754754280).

Almost surely, 2^196823815391 is an apocalyptic number.

196823815391 is a deficient number, since it is larger than the sum of its proper divisors (37290287329).

196823815391 is a wasteful number, since it uses less digits than its factorization.

196823815391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103983 (or 103976 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 56.

The spelling of 196823815391 in words is "one hundred ninety-six billion, eight hundred twenty-three million, eight hundred fifteen thousand, three hundred ninety-one".