87189811 has 2 divisors, whose sum is σ = 87189812. Its totient is φ = 87189810.

The previous prime is 87189779. The next prime is 87189827. The reversal of 87189811 is 11898178.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 87189811 - 2⁵ = 87189779 is a prime.

It is not a weakly prime, because it can be changed into another prime (87189881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43594905 + 43594906.

It is an arithmetic number, because the mean of its divisors is an integer number (43594906).

Almost surely, 2^87189811 is an apocalyptic number.

87189811 is a deficient number, since it is larger than the sum of its proper divisors (1).

87189811 is an equidigital number, since it uses as much as digits as its factorization.

87189811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 43.

The square root of 87189811 is about 9337.5484469961. The cubic root of 87189811 is about 443.4267739174.

The spelling of 87189811 in words is "eighty-seven million, one hundred eighty-nine thousand, eight hundred eleven".