18870792181 has 2 divisors, whose sum is σ = 18870792182. Its totient is φ = 18870792180.

The previous prime is 18870792179. The next prime is 18870792209. The reversal of 18870792181 is 18129707881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11075668081 + 7795124100 = 105241^2 + 88290^2 .

It is an emirp because it is prime and its reverse (18129707881) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18870792181 - 2¹ = 18870792179 is a prime.

It is a super-2 number, since 2×18870792181² (a number of 21 digits) contains 22 as substring.

Together with 18870792179, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18870792151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9435396090 + 9435396091.

It is an arithmetic number, because the mean of its divisors is an integer number (9435396091).

Almost surely, 2^18870792181 is an apocalyptic number.

It is an amenable number.

18870792181 is a deficient number, since it is larger than the sum of its proper divisors (1).

18870792181 is an equidigital number, since it uses as much as digits as its factorization.

18870792181 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 52.

The spelling of 18870792181 in words is "eighteen billion, eight hundred seventy million, seven hundred ninety-two thousand, one hundred eighty-one".