18799666699781 has 4 divisors (see below), whose sum is σ = 20508727308864. Its totient is φ = 17090606090700.

The previous prime is 18799666699777. The next prime is 18799666699783.

18799666699781 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18799666699781 - 2² = 18799666699777 is a prime.

It is a super-2 number, since 2×18799666699781² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18799666699783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 854530304525 + ... + 854530304546.

It is an arithmetic number, because the mean of its divisors is an integer number (5127181827216).

Almost surely, 2^{18799666699781} is an apocalyptic number.

18799666699781 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18799666699781 is a deficient number, since it is larger than the sum of its proper divisors (1709060609083).

18799666699781 is a wasteful number, since it uses less digits than its factorization.

18799666699781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1709060609082.

The product of its digits is 26665583616, while the sum is 92.

The spelling of 18799666699781 in words is "eighteen trillion, seven hundred ninety-nine billion, six hundred sixty-six million, six hundred ninety-nine thousand, seven hundred eighty-one".