221963894557 has 2 divisors, whose sum is σ = 221963894558. Its totient is φ = 221963894556.

The previous prime is 221963894531. The next prime is 221963894563. The reversal of 221963894557 is 755498369122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 188698147236 + 33265747321 = 434394^2 + 182389^2 .

It is a cyclic number.

It is not a de Polignac number, because 221963894557 - 2¹⁵ = 221963861789 is a prime.

It is a super-2 number, since 2×221963894557² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 221963894495 and 221963894504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221963894587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110981947278 + 110981947279.

It is an arithmetic number, because the mean of its divisors is an integer number (110981947279).

Almost surely, 2^221963894557 is an apocalyptic number.

It is an amenable number.

221963894557 is a deficient number, since it is larger than the sum of its proper divisors (1).

221963894557 is an equidigital number, since it uses as much as digits as its factorization.

221963894557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32659200, while the sum is 61.

The spelling of 221963894557 in words is "two hundred twenty-one billion, nine hundred sixty-three million, eight hundred ninety-four thousand, five hundred fifty-seven".