18374047381 has 2 divisors, whose sum is σ = 18374047382. Its totient is φ = 18374047380.

The previous prime is 18374047343. The next prime is 18374047397.

18374047381 is nontrivially palindromic in base 10.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13448113156 + 4925934225 = 115966^2 + 70185^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 18374047381 - 2¹⁹ = 18373523093 is a prime.

It is a super-2 number, since 2×18374047381² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18374447381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9187023690 + 9187023691.

It is an arithmetic number, because the mean of its divisors is an integer number (9187023691).

Almost surely, 2^18374047381 is an apocalyptic number.

It is an amenable number.

18374047381 is a deficient number, since it is larger than the sum of its proper divisors (1).

18374047381 is an equidigital number, since it uses as much as digits as its factorization.

18374047381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 451584, while the sum is 46.

The spelling of 18374047381 in words is "eighteen billion, three hundred seventy-four million, forty-seven thousand, three hundred eighty-one".