18315451381 has 8 divisors (see below), whose sum is σ = 20061549720. Its totient is φ = 16643655168.

The previous prime is 18315451369. The next prime is 18315451411.

18315451381 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 8384332356 + 9931119025 = 91566^2 + 99655^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18315451381 - 2¹³ = 18315443189 is a prime.

It is a super-2 number, since 2×18315451381² (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 (18315451321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18575016 + ... + 18576001.

It is an arithmetic number, because the mean of its divisors is an integer number (2507693715).

Almost surely, 2^18315451381 is an apocalyptic number.

It is an amenable number.

18315451381 is a deficient number, since it is larger than the sum of its proper divisors (1746098339).

18315451381 is a wasteful number, since it uses less digits than its factorization.

18315451381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37151063.

The product of its digits is 57600, while the sum is 40.

The spelling of 18315451381 in words is "eighteen billion, three hundred fifteen million, four hundred fifty-one thousand, three hundred eighty-one".