66987031109 has 2 divisors, whose sum is σ = 66987031110. Its totient is φ = 66987031108.

The previous prime is 66987031087. The next prime is 66987031117. The reversal of 66987031109 is 90113078966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51797208100 + 15189823009 = 227590^2 + 123247^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66987031109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66987031169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33493515554 + 33493515555.

It is an arithmetic number, because the mean of its divisors is an integer number (33493515555).

Almost surely, 2^66987031109 is an apocalyptic number.

It is an amenable number.

66987031109 is a deficient number, since it is larger than the sum of its proper divisors (1).

66987031109 is an equidigital number, since it uses as much as digits as its factorization.

66987031109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 489888, while the sum is 50.

The spelling of 66987031109 in words is "sixty-six billion, nine hundred eighty-seven million, thirty-one thousand, one hundred nine".