221421200002021 has 2 divisors, whose sum is σ = 221421200002022. Its totient is φ = 221421200002020.

The previous prime is 221421200002003. The next prime is 221421200002033. The reversal of 221421200002021 is 120200002124122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 140974920437796 + 80446279564225 = 11873286^2 + 8969185^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221421200002021 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221421200002021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221421200002921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110710600001010 + 110710600001011.

It is an arithmetic number, because the mean of its divisors is an integer number (110710600001011).

Almost surely, 2^{221421200002021} is an apocalyptic number.

It is an amenable number.

221421200002021 is a deficient number, since it is larger than the sum of its proper divisors (1).

221421200002021 is an equidigital number, since it uses as much as digits as its factorization.

221421200002021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 221421200002021 its reverse (120200002124122), we get a palindrome (341621202126143).

The spelling of 221421200002021 in words is "two hundred twenty-one trillion, four hundred twenty-one billion, two hundred million, two thousand, twenty-one".