819969808969918 has 16 divisors (see below), whose sum is σ = 1234772830592784. Its totient is φ = 408378948904960.

The previous prime is 819969808969891. The next prime is 819969808969931.

819969808969918 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1181080 + ... + 40513387.

It is an arithmetic number, because the mean of its divisors is an integer number (77173301912049).

Almost surely, 2^{819969808969918} is an apocalyptic number.

819969808969918 is a deficient number, since it is larger than the sum of its proper divisors (414803021622866).

819969808969918 is a wasteful number, since it uses less digits than its factorization.

819969808969918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41732987.

The product of its (nonzero) digits is 78364164096, while the sum is 100.

The spelling of 819969808969918 in words is "eight hundred nineteen trillion, nine hundred sixty-nine billion, eight hundred eight million, nine hundred sixty-nine thousand, nine hundred eighteen".