402221105821 has 2 divisors, whose sum is σ = 402221105822. Its totient is φ = 402221105820.

The previous prime is 402221105809. The next prime is 402221105827. The reversal of 402221105821 is 128501122204.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 238773936025 + 163447169796 = 488645^2 + 404286^2 .

It is a cyclic number.

It is not a de Polignac number, because 402221105821 - 2¹⁵ = 402221073053 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 402221105821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (402221105827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201110552910 + 201110552911.

It is an arithmetic number, because the mean of its divisors is an integer number (201110552911).

Almost surely, 2^402221105821 is an apocalyptic number.

It is an amenable number.

402221105821 is a deficient number, since it is larger than the sum of its proper divisors (1).

402221105821 is an equidigital number, since it uses as much as digits as its factorization.

402221105821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2560, while the sum is 28.

The spelling of 402221105821 in words is "four hundred two billion, two hundred twenty-one million, one hundred five thousand, eight hundred twenty-one".