1664105987 has 2 divisors, whose sum is σ = 1664105988. Its totient is φ = 1664105986.

The previous prime is 1664105941. The next prime is 1664106049. The reversal of 1664105987 is 7895014661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1664105987 - 2⁸ = 1664105731 is a prime.

It is a zygodrome in base 2.

It is not a weakly prime, because it can be changed into another prime (1664105887) 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, 832052993 + 832052994.

It is an arithmetic number, because the mean of its divisors is an integer number (832052994).

Almost surely, 2^1664105987 is an apocalyptic number.

1664105987 is a deficient number, since it is larger than the sum of its proper divisors (1).

1664105987 is an equidigital number, since it uses as much as digits as its factorization.

1664105987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 362880, while the sum is 47.

The square root of 1664105987 is about 40793.4551981075. The cubic root of 1664105987 is about 1185.0235859691.

The spelling of 1664105987 in words is "one billion, six hundred sixty-four million, one hundred five thousand, nine hundred eighty-seven".