18354845381 has 4 divisors (see below), whose sum is σ = 18356114700. Its totient is φ = 18353576064.

The previous prime is 18354845359. The next prime is 18354845419.

18354845381 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12799528225 + 5555317156 = 113135^2 + 74534^2 .

It is a cyclic number.

It is not a de Polignac number, because 18354845381 - 2¹⁴ = 18354828997 is a prime.

It is a super-2 number, since 2×18354845381² (a number of 21 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 (18354845321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 612716 + ... + 641973.

It is an arithmetic number, because the mean of its divisors is an integer number (4589028675).

Almost surely, 2^18354845381 is an apocalyptic number.

It is an amenable number.

18354845381 is a deficient number, since it is larger than the sum of its proper divisors (1269319).

18354845381 is a wasteful number, since it uses less digits than its factorization.

18354845381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1269318.

The product of its digits is 1843200, while the sum is 50.

The spelling of 18354845381 in words is "eighteen billion, three hundred fifty-four million, eight hundred forty-five thousand, three hundred eighty-one".