819081994 has 8 divisors (see below), whose sum is σ = 1235725380. Its totient is φ = 407173536.

The previous prime is 819081971. The next prime is 819081997. The reversal of 819081994 is 499180918.

It can be written as a sum of positive squares in 2 ways, for example, as 818703769 + 378225 = 28613^2 + 615^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (819081997) 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, 1183299 + ... + 1183990.

Almost surely, 2^819081994 is an apocalyptic number.

819081994 is a deficient number, since it is larger than the sum of its proper divisors (416643386).

819081994 is a wasteful number, since it uses less digits than its factorization.

819081994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2367464.

The product of its (nonzero) digits is 186624, while the sum is 49.

The square root of 819081994 is about 28619.6085577703. The cubic root of 819081994 is about 935.6407454720.

The spelling of 819081994 in words is "eight hundred nineteen million, eighty-one thousand, nine hundred ninety-four".