221421255544717 has 2 divisors, whose sum is σ = 221421255544718. Its totient is φ = 221421255544716.

The previous prime is 221421255544681. The next prime is 221421255544787. The reversal of 221421255544717 is 717445552124122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 221098729233321 + 322526311396 = 14869389^2 + 567914^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221421255544717 is a prime.

It is a super-2 number, since 2×221421255544717² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221421255544787) 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, 110710627772358 + 110710627772359.

It is an arithmetic number, because the mean of its divisors is an integer number (110710627772359).

Almost surely, 2^{221421255544717} is an apocalyptic number.

It is an amenable number.

221421255544717 is a deficient number, since it is larger than the sum of its proper divisors (1).

221421255544717 is an equidigital number, since it uses as much as digits as its factorization.

221421255544717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6272000, while the sum is 52.

The spelling of 221421255544717 in words is "two hundred twenty-one trillion, four hundred twenty-one billion, two hundred fifty-five million, five hundred forty-four thousand, seven hundred seventeen".