819393939 has 96 divisors (see below), whose sum is σ = 1522160640. Its totient is φ = 413247744.

The previous prime is 819393937. The next prime is 819393961. The reversal of 819393939 is 939393918.

It is not a de Polignac number, because 819393939 - 2¹ = 819393937 is a prime.

819393939 is a modest number, since divided by 393939 gives 819 as remainder.

It is not an unprimeable number, because it can be changed into a prime (819393937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1866282 + ... + 1866720.

It is an arithmetic number, because the mean of its divisors is an integer number (15855840).

Almost surely, 2^819393939 is an apocalyptic number.

819393939 is a deficient number, since it is larger than the sum of its proper divisors (702766701).

819393939 is a wasteful number, since it uses less digits than its factorization.

819393939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 561 (or 558 counting only the distinct ones).

The product of its digits is 1417176, while the sum is 54.

The square root of 819393939 is about 28625.0578864044. The cubic root of 819393939 is about 935.7595090838.

The spelling of 819393939 in words is "eight hundred nineteen million, three hundred ninety-three thousand, nine hundred thirty-nine".