1639266803081 has 2 divisors, whose sum is σ = 1639266803082. Its totient is φ = 1639266803080.

The previous prime is 1639266803071. The next prime is 1639266803117. The reversal of 1639266803081 is 1803086629361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1461823665481 + 177443137600 = 1209059^2 + 421240^2 .

It is an emirp because it is prime and its reverse (1803086629361) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1639266803081 is a prime.

It is a super-2 number, since 2×1639266803081² (a number of 25 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1639266803071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 819633401540 + 819633401541.

It is an arithmetic number, because the mean of its divisors is an integer number (819633401541).

Almost surely, 2^{1639266803081} is an apocalyptic number.

It is an amenable number.

1639266803081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1639266803081 is an equidigital number, since it uses as much as digits as its factorization.

1639266803081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2239488, while the sum is 53.

The spelling of 1639266803081 in words is "one trillion, six hundred thirty-nine billion, two hundred sixty-six million, eight hundred three thousand, eighty-one".