1640680290121 has 2 divisors, whose sum is σ = 1640680290122. Its totient is φ = 1640680290120.

The previous prime is 1640680290103. The next prime is 1640680290173. The reversal of 1640680290121 is 1210920860461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1615596065721 + 25084224400 = 1271061^2 + 158380^2 .

It is a cyclic number.

It is not a de Polignac number, because 1640680290121 - 2⁷ = 1640680289993 is a prime.

It is not a weakly prime, because it can be changed into another prime (1640680090121) 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, 820340145060 + 820340145061.

It is an arithmetic number, because the mean of its divisors is an integer number (820340145061).

Almost surely, 2^{1640680290121} is an apocalyptic number.

It is an amenable number.

1640680290121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640680290121 is an equidigital number, since it uses as much as digits as its factorization.

1640680290121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 41472, while the sum is 40.

The spelling of 1640680290121 in words is "one trillion, six hundred forty billion, six hundred eighty million, two hundred ninety thousand, one hundred twenty-one".