221420434321 has 2 divisors, whose sum is σ = 221420434322. Its totient is φ = 221420434320.

The previous prime is 221420434307. The next prime is 221420434343. The reversal of 221420434321 is 123434024122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 139361102721 + 82059331600 = 373311^2 + 286460^2 .

It is a cyclic number.

It is not a de Polignac number, because 221420434321 - 2¹¹ = 221420432273 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221420434321.

It is not a weakly prime, because it can be changed into another prime (221420434381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110710217160 + 110710217161.

It is an arithmetic number, because the mean of its divisors is an integer number (110710217161).

Almost surely, 2^221420434321 is an apocalyptic number.

It is an amenable number.

221420434321 is a deficient number, since it is larger than the sum of its proper divisors (1).

221420434321 is an equidigital number, since it uses as much as digits as its factorization.

221420434321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9216, while the sum is 28.

Adding to 221420434321 its reverse (123434024122), we get a palindrome (344854458443).

The spelling of 221420434321 in words is "two hundred twenty-one billion, four hundred twenty million, four hundred thirty-four thousand, three hundred twenty-one".