221534403655867 has 2 divisors, whose sum is σ = 221534403655868. Its totient is φ = 221534403655866.

The previous prime is 221534403655861. The next prime is 221534403655871. The reversal of 221534403655867 is 768556304435122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221534403655867 is a prime.

It is not a weakly prime, because it can be changed into another prime (221534403655861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110767201827933 + 110767201827934.

It is an arithmetic number, because the mean of its divisors is an integer number (110767201827934).

Almost surely, 2^{221534403655867} is an apocalyptic number.

221534403655867 is a deficient number, since it is larger than the sum of its proper divisors (1).

221534403655867 is an equidigital number, since it uses as much as digits as its factorization.

221534403655867 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 145152000, while the sum is 61.

The spelling of 221534403655867 in words is "two hundred twenty-one trillion, five hundred thirty-four billion, four hundred three million, six hundred fifty-five thousand, eight hundred sixty-seven".