1994487561878 has 16 divisors (see below), whose sum is σ = 3449379250080. Its totient is φ = 847215954816.

The previous prime is 1994487561877. The next prime is 1994487561953. The reversal of 1994487561878 is 8781657844991.

It is a junction number, because it is equal to n+sod(n) for n = 1994487561799 and 1994487561808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1994487561877) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 630367433 + ... + 630370596.

It is an arithmetic number, because the mean of its divisors is an integer number (215586203130).

Almost surely, 2^{1994487561878} is an apocalyptic number.

1994487561878 is a deficient number, since it is larger than the sum of its proper divisors (1454891688202).

1994487561878 is a wasteful number, since it uses less digits than its factorization.

1994487561878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1260738151.

The product of its digits is 975421440, while the sum is 77.

The spelling of 1994487561878 in words is "one trillion, nine hundred ninety-four billion, four hundred eighty-seven million, five hundred sixty-one thousand, eight hundred seventy-eight".