1685269814981 has 2 divisors, whose sum is σ = 1685269814982. Its totient is φ = 1685269814980.

The previous prime is 1685269814923. The next prime is 1685269814983. The reversal of 1685269814981 is 1894189625861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1301347066756 + 383922748225 = 1140766^2 + 619615^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1685269814981 is a prime.

It is a super-2 number, since 2×1685269814981² (a number of 25 digits) contains 22 as substring.

Together with 1685269814983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1685269814983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 842634907490 + 842634907491.

It is an arithmetic number, because the mean of its divisors is an integer number (842634907491).

Almost surely, 2^{1685269814981} is an apocalyptic number.

It is an amenable number.

1685269814981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1685269814981 is an equidigital number, since it uses as much as digits as its factorization.

1685269814981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 59719680, while the sum is 68.

The spelling of 1685269814981 in words is "one trillion, six hundred eighty-five billion, two hundred sixty-nine million, eight hundred fourteen thousand, nine hundred eighty-one".