1643089849693 has 2 divisors, whose sum is σ = 1643089849694. Its totient is φ = 1643089849692.

The previous prime is 1643089849663. The next prime is 1643089849699. The reversal of 1643089849693 is 3969489803461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1285894764729 + 357195084964 = 1133973^2 + 597658^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1643089849693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1643089849699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821544924846 + 821544924847.

It is an arithmetic number, because the mean of its divisors is an integer number (821544924847).

Almost surely, 2^{1643089849693} is an apocalyptic number.

It is an amenable number.

1643089849693 is a deficient number, since it is larger than the sum of its proper divisors (1).

1643089849693 is an equidigital number, since it uses as much as digits as its factorization.

1643089849693 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 241864704, while the sum is 70.

The spelling of 1643089849693 in words is "one trillion, six hundred forty-three billion, eighty-nine million, eight hundred forty-nine thousand, six hundred ninety-three".