221728906967 has 2 divisors, whose sum is σ = 221728906968. Its totient is φ = 221728906966.

The previous prime is 221728906939. The next prime is 221728906979. The reversal of 221728906967 is 769609827122.

It is a happy number.

221728906967 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221728906967 - 2¹⁴ = 221728890583 is a prime.

It is a super-2 number, since 2×221728906967² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221728906667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110864453483 + 110864453484.

It is an arithmetic number, because the mean of its divisors is an integer number (110864453484).

Almost surely, 2^221728906967 is an apocalyptic number.

221728906967 is a deficient number, since it is larger than the sum of its proper divisors (1).

221728906967 is an equidigital number, since it uses as much as digits as its factorization.

221728906967 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9144576, while the sum is 59.

The spelling of 221728906967 in words is "two hundred twenty-one billion, seven hundred twenty-eight million, nine hundred six thousand, nine hundred sixty-seven".