1820445442769 has 2 divisors, whose sum is σ = 1820445442770. Its totient is φ = 1820445442768.

The previous prime is 1820445442597. The next prime is 1820445442787. The reversal of 1820445442769 is 9672445440281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1557366723025 + 263078719744 = 1247945^2 + 512912^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1820445442769 is a prime.

It is a super-2 number, since 2×1820445442769² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1820445412769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910222721384 + 910222721385.

It is an arithmetic number, because the mean of its divisors is an integer number (910222721385).

Almost surely, 2^{1820445442769} is an apocalyptic number.

It is an amenable number.

1820445442769 is a deficient number, since it is larger than the sum of its proper divisors (1).

1820445442769 is an equidigital number, since it uses as much as digits as its factorization.

1820445442769 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15482880, while the sum is 56.

The spelling of 1820445442769 in words is "one trillion, eight hundred twenty billion, four hundred forty-five million, four hundred forty-two thousand, seven hundred sixty-nine".