18871900237 has 2 divisors, whose sum is σ = 18871900238. Its totient is φ = 18871900236.

The previous prime is 18871900231. The next prime is 18871900241. The reversal of 18871900237 is 73200917881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18608779396 + 263120841 = 136414^2 + 16221^2 .

It is a cyclic number.

It is not a de Polignac number, because 18871900237 - 2⁷ = 18871900109 is a prime.

It is a super-2 number, since 2×18871900237² (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 (18871900231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9435950118 + 9435950119.

It is an arithmetic number, because the mean of its divisors is an integer number (9435950119).

Almost surely, 2^18871900237 is an apocalyptic number.

It is an amenable number.

18871900237 is a deficient number, since it is larger than the sum of its proper divisors (1).

18871900237 is an equidigital number, since it uses as much as digits as its factorization.

18871900237 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 169344, while the sum is 46.

The spelling of 18871900237 in words is "eighteen billion, eight hundred seventy-one million, nine hundred thousand, two hundred thirty-seven".