18347744774381 has 16 divisors (see below), whose sum is σ = 21795704078400. Its totient is φ = 15256992844800.

The previous prime is 18347744774369. The next prime is 18347744774393.

18347744774381 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (18347744774369) and next prime (18347744774393).

It is a cyclic number.

It is not a de Polignac number, because 18347744774381 - 2²² = 18347740580077 is a prime.

It is a super-2 number, since 2×18347744774381² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18347744774981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1513584500 + ... + 1513596621.

It is an arithmetic number, because the mean of its divisors is an integer number (1362231504900).

Almost surely, 2^{18347744774381} is an apocalyptic number.

18347744774381 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18347744774381 is a deficient number, since it is larger than the sum of its proper divisors (3447959304019).

18347744774381 is a wasteful number, since it uses less digits than its factorization.

18347744774381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3027181180.

The product of its digits is 354041856, while the sum is 68.

The spelling of 18347744774381 in words is "eighteen trillion, three hundred forty-seven billion, seven hundred forty-four million, seven hundred seventy-four thousand, three hundred eighty-one".