221421389407 has 2 divisors, whose sum is σ = 221421389408. Its totient is φ = 221421389406.

The previous prime is 221421389393. The next prime is 221421389429. The reversal of 221421389407 is 704983124122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221421389407 - 2¹¹ = 221421387359 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221421389437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110710694703 + 110710694704.

It is an arithmetic number, because the mean of its divisors is an integer number (110710694704).

Almost surely, 2^221421389407 is an apocalyptic number.

221421389407 is a deficient number, since it is larger than the sum of its proper divisors (1).

221421389407 is an equidigital number, since it uses as much as digits as its factorization.

221421389407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 193536, while the sum is 43.

The spelling of 221421389407 in words is "two hundred twenty-one billion, four hundred twenty-one million, three hundred eighty-nine thousand, four hundred seven".