1642801497809 has 2 divisors, whose sum is σ = 1642801497810. Its totient is φ = 1642801497808.

The previous prime is 1642801497803. The next prime is 1642801497823. The reversal of 1642801497809 is 9087941082461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1633404134209 + 9397363600 = 1278047^2 + 96940^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1642801497809 is a prime.

It is a super-3 number, since 3×1642801497809³ (a number of 38 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (1642801497803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821400748904 + 821400748905.

It is an arithmetic number, because the mean of its divisors is an integer number (821400748905).

Almost surely, 2^{1642801497809} is an apocalyptic number.

It is an amenable number.

1642801497809 is a deficient number, since it is larger than the sum of its proper divisors (1).

1642801497809 is an equidigital number, since it uses as much as digits as its factorization.

1642801497809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6967296, while the sum is 59.

The spelling of 1642801497809 in words is "one trillion, six hundred forty-two billion, eight hundred one million, four hundred ninety-seven thousand, eight hundred nine".