221321454486817 has 2 divisors, whose sum is σ = 221321454486818. Its totient is φ = 221321454486816.

The previous prime is 221321454486757. The next prime is 221321454486833. The reversal of 221321454486817 is 718684454123122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 219900456979681 + 1420997507136 = 14829041^2 + 1192056^2 .

It is a cyclic number.

It is not a de Polignac number, because 221321454486817 - 2¹¹ = 221321454484769 is a prime.

It is not a weakly prime, because it can be changed into another prime (221321454406817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110660727243408 + 110660727243409.

It is an arithmetic number, because the mean of its divisors is an integer number (110660727243409).

Almost surely, 2^{221321454486817} is an apocalyptic number.

It is an amenable number.

221321454486817 is a deficient number, since it is larger than the sum of its proper divisors (1).

221321454486817 is an equidigital number, since it uses as much as digits as its factorization.

221321454486817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20643840, while the sum is 58.

The spelling of 221321454486817 in words is "two hundred twenty-one trillion, three hundred twenty-one billion, four hundred fifty-four million, four hundred eighty-six thousand, eight hundred seventeen".