819969918 has 32 divisors (see below), whose sum is σ = 1712800512. Its totient is φ = 261201600.

The previous prime is 819969883. The next prime is 819969929.

It is a happy number.

819969918 is nontrivially palindromic in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 209338 + ... + 213218.

It is an arithmetic number, because the mean of its divisors is an integer number (53525016).

Almost surely, 2^819969918 is an apocalyptic number.

819969918 is an abundant number, since it is smaller than the sum of its proper divisors (892830594).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

819969918 is a wasteful number, since it uses less digits than its factorization.

819969918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5440.

The product of its digits is 2519424, while the sum is 60.

The square root of 819969918 is about 28635.1168672314. The cubic root of 819969918 is about 935.9787164603.

The spelling of 819969918 in words is "eight hundred nineteen million, nine hundred sixty-nine thousand, nine hundred eighteen".