80844808021 has 2 divisors, whose sum is σ = 80844808022. Its totient is φ = 80844808020.

The previous prime is 80844807991. The next prime is 80844808073. The reversal of 80844808021 is 12080844808.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66609931921 + 14234876100 = 258089^2 + 119310^2 .

It is a cyclic number.

It is not a de Polignac number, because 80844808021 - 2⁷ = 80844807893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (80844808091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40422404010 + 40422404011.

It is an arithmetic number, because the mean of its divisors is an integer number (40422404011).

Almost surely, 2^80844808021 is an apocalyptic number.

It is an amenable number.

80844808021 is a deficient number, since it is larger than the sum of its proper divisors (1).

80844808021 is an equidigital number, since it uses as much as digits as its factorization.

80844808021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 131072, while the sum is 43.

The spelling of 80844808021 in words is "eighty billion, eight hundred forty-four million, eight hundred eight thousand, twenty-one".