18501683381 has 2 divisors, whose sum is σ = 18501683382. Its totient is φ = 18501683380.

The previous prime is 18501683353. The next prime is 18501683383. The reversal of 18501683381 is 18338610581.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18482402500 + 19280881 = 135950^2 + 4391^2 .

It is a cyclic number.

It is not a de Polignac number, because 18501683381 - 2²⁶ = 18434574517 is a prime.

It is a super-2 number, since 2×18501683381² (a number of 21 digits) contains 22 as substring.

Together with 18501683383, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18501683383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9250841690 + 9250841691.

It is an arithmetic number, because the mean of its divisors is an integer number (9250841691).

Almost surely, 2^18501683381 is an apocalyptic number.

It is an amenable number.

18501683381 is a deficient number, since it is larger than the sum of its proper divisors (1).

18501683381 is an equidigital number, since it uses as much as digits as its factorization.

18501683381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 138240, while the sum is 44.

The spelling of 18501683381 in words is "eighteen billion, five hundred one million, six hundred eighty-three thousand, three hundred eighty-one".