87391789189 has 2 divisors, whose sum is σ = 87391789190. Its totient is φ = 87391789188.

The previous prime is 87391789031. The next prime is 87391789201. The reversal of 87391789189 is 98198719378.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64849169025 + 22542620164 = 254655^2 + 150142^2 .

It is a cyclic number.

It is not a de Polignac number, because 87391789189 - 2⁹ = 87391788677 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87391786189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43695894594 + 43695894595.

It is an arithmetic number, because the mean of its divisors is an integer number (43695894595).

Almost surely, 2^87391789189 is an apocalyptic number.

It is an amenable number.

87391789189 is a deficient number, since it is larger than the sum of its proper divisors (1).

87391789189 is an equidigital number, since it uses as much as digits as its factorization.

87391789189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54867456, while the sum is 70.

The spelling of 87391789189 in words is "eighty-seven billion, three hundred ninety-one million, seven hundred eighty-nine thousand, one hundred eighty-nine".