18938488381 has 2 divisors, whose sum is σ = 18938488382. Its totient is φ = 18938488380.

The previous prime is 18938488339. The next prime is 18938488399. The reversal of 18938488381 is 18388483981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18580143481 + 358344900 = 136309^2 + 18930^2 .

It is a cyclic number.

It is not a de Polignac number, because 18938488381 - 2¹⁹ = 18937964093 is a prime.

It is a super-2 number, since 2×18938488381² (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 (18938488301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9469244190 + 9469244191.

It is an arithmetic number, because the mean of its divisors is an integer number (9469244191).

Almost surely, 2^18938488381 is an apocalyptic number.

It is an amenable number.

18938488381 is a deficient number, since it is larger than the sum of its proper divisors (1).

18938488381 is an equidigital number, since it uses as much as digits as its factorization.

18938488381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10616832, while the sum is 61.

The spelling of 18938488381 in words is "eighteen billion, nine hundred thirty-eight million, four hundred eighty-eight thousand, three hundred eighty-one".