87321139 has 2 divisors, whose sum is σ = 87321140. Its totient is φ = 87321138.

The previous prime is 87321109. The next prime is 87321151. The reversal of 87321139 is 93112378.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 87321139 - 2⁷ = 87321011 is a prime.

It is not a weakly prime, because it can be changed into another prime (87321109) 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, 43660569 + 43660570.

It is an arithmetic number, because the mean of its divisors is an integer number (43660570).

Almost surely, 2^87321139 is an apocalyptic number.

87321139 is a deficient number, since it is larger than the sum of its proper divisors (1).

87321139 is an equidigital number, since it uses as much as digits as its factorization.

87321139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 34.

The square root of 87321139 is about 9344.5780536095. The cubic root of 87321139 is about 443.6492966220.

The spelling of 87321139 in words is "eighty-seven million, three hundred twenty-one thousand, one hundred thirty-nine".