445367811821 has 2 divisors, whose sum is σ = 445367811822. Its totient is φ = 445367811820.

The previous prime is 445367811773. The next prime is 445367811901. The reversal of 445367811821 is 128118763544.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 414460413796 + 30907398025 = 643786^2 + 175805^2 .

It is a cyclic number.

It is not a de Polignac number, because 445367811821 - 2³⁰ = 444294069997 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 445367811821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (445367871821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 222683905910 + 222683905911.

It is an arithmetic number, because the mean of its divisors is an integer number (222683905911).

Almost surely, 2^445367811821 is an apocalyptic number.

It is an amenable number.

445367811821 is a deficient number, since it is larger than the sum of its proper divisors (1).

445367811821 is an equidigital number, since it uses as much as digits as its factorization.

445367811821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1290240, while the sum is 50.

The spelling of 445367811821 in words is "four hundred forty-five billion, three hundred sixty-seven million, eight hundred eleven thousand, eight hundred twenty-one".