1808227419721 has 2 divisors, whose sum is σ = 1808227419722. Its totient is φ = 1808227419720.

The previous prime is 1808227419703. The next prime is 1808227419793. The reversal of 1808227419721 is 1279147228081.

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., 1804282951696 + 3944468025 = 1343236^2 + 62805^2 .

It is a cyclic number.

It is not a de Polignac number, because 1808227419721 - 2⁵ = 1808227419689 is a prime.

It is not a weakly prime, because it can be changed into another prime (1808227419701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 904113709860 + 904113709861.

It is an arithmetic number, because the mean of its divisors is an integer number (904113709861).

Almost surely, 2^{1808227419721} is an apocalyptic number.

It is an amenable number.

1808227419721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1808227419721 is an equidigital number, since it uses as much as digits as its factorization.

1808227419721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 903168, while the sum is 52.

The spelling of 1808227419721 in words is "one trillion, eight hundred eight billion, two hundred twenty-seven million, four hundred nineteen thousand, seven hundred twenty-one".