18799099781 has 24 divisors (see below), whose sum is σ = 24164640192. Its totient is φ = 14307955200.

The previous prime is 18799099777. The next prime is 18799099799.

18799099781 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 18799099781 - 2² = 18799099777 is a prime.

It is a super-2 number, since 2×18799099781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18799099741) 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, 221660 + ... + 294501.

It is an arithmetic number, because the mean of its divisors is an integer number (1006860008).

Almost surely, 2^18799099781 is an apocalyptic number.

18799099781 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18799099781 is a deficient number, since it is larger than the sum of its proper divisors (5365540411).

18799099781 is a wasteful number, since it uses less digits than its factorization.

18799099781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 516233 (or 516222 counting only the distinct ones).

The product of its (nonzero) digits is 20575296, while the sum is 68.

The spelling of 18799099781 in words is "eighteen billion, seven hundred ninety-nine million, ninety-nine thousand, seven hundred eighty-one".