1685001851849 has 2 divisors, whose sum is σ = 1685001851850. Its totient is φ = 1685001851848.

The previous prime is 1685001851843. The next prime is 1685001851917. The reversal of 1685001851849 is 9481581005861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1060004089225 + 624997762624 = 1029565^2 + 790568^2 .

It is a cyclic number.

It is not a de Polignac number, because 1685001851849 - 2²⁰ = 1685000803273 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1685001851794 and 1685001851803.

It is not a weakly prime, because it can be changed into another prime (1685001851843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 842500925924 + 842500925925.

It is an arithmetic number, because the mean of its divisors is an integer number (842500925925).

Almost surely, 2^{1685001851849} is an apocalyptic number.

It is an amenable number.

1685001851849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1685001851849 is an equidigital number, since it uses as much as digits as its factorization.

1685001851849 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2764800, while the sum is 56.

The spelling of 1685001851849 in words is "one trillion, six hundred eighty-five billion, one million, eight hundred fifty-one thousand, eight hundred forty-nine".