1993378733991 has 24 divisors (see below), whose sum is σ = 2883366180864. Its totient is φ = 1327055168400.

The previous prime is 1993378733989. The next prime is 1993378734031.

1993378733991 is a `hidden beast` number, since 19 + 93 + 3 + 78 + 73 + 399 + 1 = 666.

1993378733991 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1993378733991 - 2¹ = 1993378733989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1993378733921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19704160 + ... + 19805066.

It is an arithmetic number, because the mean of its divisors is an integer number (120140257536).

Almost surely, 2^{1993378733991} is an apocalyptic number.

1993378733991 is a deficient number, since it is larger than the sum of its proper divisors (889987446873).

1993378733991 is a wasteful number, since it uses less digits than its factorization.

1993378733991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103971 (or 103968 counting only the distinct ones).

The product of its digits is 208324872, while the sum is 72.

The spelling of 1993378733991 in words is "one trillion, nine hundred ninety-three billion, three hundred seventy-eight million, seven hundred thirty-three thousand, nine hundred ninety-one".