18987881053 has 2 divisors, whose sum is σ = 18987881054. Its totient is φ = 18987881052.

The previous prime is 18987881027. The next prime is 18987881057. The reversal of 18987881053 is 35018878981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16466535684 + 2521345369 = 128322^2 + 50213^2 .

It is an emirp because it is prime and its reverse (35018878981) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18987881053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18987881057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9493940526 + 9493940527.

It is an arithmetic number, because the mean of its divisors is an integer number (9493940527).

Almost surely, 2^18987881053 is an apocalyptic number.

It is an amenable number.

18987881053 is a deficient number, since it is larger than the sum of its proper divisors (1).

18987881053 is an equidigital number, since it uses as much as digits as its factorization.

18987881053 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3870720, while the sum is 58.

The spelling of 18987881053 in words is "eighteen billion, nine hundred eighty-seven million, eight hundred eighty-one thousand, fifty-three".