187817602081 has 2 divisors, whose sum is σ = 187817602082. Its totient is φ = 187817602080.

The previous prime is 187817602019. The next prime is 187817602087. The reversal of 187817602081 is 180206718781.

187817602081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 187524507681 + 293094400 = 433041^2 + 17120^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-187817602081 is a prime.

It is a super-2 number, since 2×187817602081² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (187817602087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93908801040 + 93908801041.

It is an arithmetic number, because the mean of its divisors is an integer number (93908801041).

Almost surely, 2^187817602081 is an apocalyptic number.

It is an amenable number.

187817602081 is a deficient number, since it is larger than the sum of its proper divisors (1).

187817602081 is an equidigital number, since it uses as much as digits as its factorization.

187817602081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 301056, while the sum is 49.

The spelling of 187817602081 in words is "one hundred eighty-seven billion, eight hundred seventeen million, six hundred two thousand, eighty-one".