221655006321317 has 2 divisors, whose sum is σ = 221655006321318. Its totient is φ = 221655006321316.

The previous prime is 221655006321253. The next prime is 221655006321341. The reversal of 221655006321317 is 713123600556122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 196717427308801 + 24937579012516 = 14025599^2 + 4993754^2 .

It is a cyclic number.

It is not a de Polignac number, because 221655006321317 - 2⁶ = 221655006321253 is a prime.

It is a super-2 number, since 2×221655006321317² (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 (221655006221317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110827503160658 + 110827503160659.

It is an arithmetic number, because the mean of its divisors is an integer number (110827503160659).

Almost surely, 2^{221655006321317} is an apocalyptic number.

It is an amenable number.

221655006321317 is a deficient number, since it is larger than the sum of its proper divisors (1).

221655006321317 is an equidigital number, since it uses as much as digits as its factorization.

221655006321317 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 453600, while the sum is 44.

Adding to 221655006321317 its reverse (713123600556122), we get a palindrome (934778606877439).

The spelling of 221655006321317 in words is "two hundred twenty-one trillion, six hundred fifty-five billion, six million, three hundred twenty-one thousand, three hundred seventeen".