187684381 has 2 divisors, whose sum is σ = 187684382. Its totient is φ = 187684380.

The previous prime is 187684363. The next prime is 187684391. The reversal of 187684381 is 183486781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 109202500 + 78481881 = 10450^2 + 8859^2 .

It is a cyclic number.

It is not a de Polignac number, because 187684381 - 2⁵ = 187684349 is a prime.

It is a super-2 number, since 2×187684381² = 70450853742706322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (187684351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93842190 + 93842191.

It is an arithmetic number, because the mean of its divisors is an integer number (93842191).

Almost surely, 2^187684381 is an apocalyptic number.

It is an amenable number.

187684381 is a deficient number, since it is larger than the sum of its proper divisors (1).

187684381 is an equidigital number, since it uses as much as digits as its factorization.

187684381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 258048, while the sum is 46.

The square root of 187684381 is about 13699.7949254724. The cubic root of 187684381 is about 572.5446718636.

The spelling of 187684381 in words is "one hundred eighty-seven million, six hundred eighty-four thousand, three hundred eighty-one".