408644220421 has 2 divisors, whose sum is σ = 408644220422. Its totient is φ = 408644220420.

The previous prime is 408644220401. The next prime is 408644220521. The reversal of 408644220421 is 124022446804.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 258049776196 + 150594444225 = 507986^2 + 388065^2 .

It is a cyclic number.

It is not a de Polignac number, because 408644220421 - 2¹¹ = 408644218373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (408644220401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 204322110210 + 204322110211.

It is an arithmetic number, because the mean of its divisors is an integer number (204322110211).

Almost surely, 2^408644220421 is an apocalyptic number.

It is an amenable number.

408644220421 is a deficient number, since it is larger than the sum of its proper divisors (1).

408644220421 is an equidigital number, since it uses as much as digits as its factorization.

408644220421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 98304, while the sum is 37.

The spelling of 408644220421 in words is "four hundred eight billion, six hundred forty-four million, two hundred twenty thousand, four hundred twenty-one".