18874637281 has 2 divisors, whose sum is σ = 18874637282. Its totient is φ = 18874637280.

The previous prime is 18874637239. The next prime is 18874637293. The reversal of 18874637281 is 18273647881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13539649600 + 5334987681 = 116360^2 + 73041^2 .

It is a cyclic number.

It is not a de Polignac number, because 18874637281 - 2⁹ = 18874636769 is a prime.

It is a super-2 number, since 2×18874637281² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18974637281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9437318640 + 9437318641.

It is an arithmetic number, because the mean of its divisors is an integer number (9437318641).

Almost surely, 2^18874637281 is an apocalyptic number.

It is an amenable number.

18874637281 is a deficient number, since it is larger than the sum of its proper divisors (1).

18874637281 is an equidigital number, since it uses as much as digits as its factorization.

18874637281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3612672, while the sum is 55.

The spelling of 18874637281 in words is "eighteen billion, eight hundred seventy-four million, six hundred thirty-seven thousand, two hundred eighty-one".