1994778239994 has 12 divisors (see below), whose sum is σ = 4322019520026. Its totient is φ = 664926079992.

The previous prime is 1994778239983. The next prime is 1994778240001. The reversal of 1994778239994 is 4999328774991.

1994778239994 is a `hidden beast` number, since 199 + 47 + 78 + 239 + 9 + 94 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1122300815769 + 872477424225 = 1059387^2 + 934065^2 .

It is a super-3 number, since 3×1994778239994³ (a number of 38 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 55410506649 + ... + 55410506684.

Almost surely, 2^{1994778239994} is an apocalyptic number.

1994778239994 is an abundant number, since it is smaller than the sum of its proper divisors (2327241280032).

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

1994778239994 is a wasteful number, since it uses less digits than its factorization.

1994778239994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110821013341 (or 110821013338 counting only the distinct ones).

The product of its digits is 2222131968, while the sum is 81.

The spelling of 1994778239994 in words is "one trillion, nine hundred ninety-four billion, seven hundred seventy-eight million, two hundred thirty-nine thousand, nine hundred ninety-four".