18352381 has 2 divisors, whose sum is σ = 18352382. Its totient is φ = 18352380.

The previous prime is 18352361. The next prime is 18352387. The reversal of 18352381 is 18325381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16475481 + 1876900 = 4059^2 + 1370^2 .

It is an emirp because it is prime and its reverse (18325381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18352381 - 2⁵ = 18352349 is a prime.

It is a super-2 number, since 2×18352381² = 673619776738322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18352387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9176190 + 9176191.

It is an arithmetic number, because the mean of its divisors is an integer number (9176191).

Almost surely, 2^18352381 is an apocalyptic number.

It is an amenable number.

18352381 is a deficient number, since it is larger than the sum of its proper divisors (1).

18352381 is an equidigital number, since it uses as much as digits as its factorization.

18352381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 31.

The square root of 18352381 is about 4283.9679037080. The cubic root of 18352381 is about 263.7732835101.

Subtracting from 18352381 its reverse (18325381), we obtain a cube (27000 = 30³).

The spelling of 18352381 in words is "eighteen million, three hundred fifty-two thousand, three hundred eighty-one".