221664121093 has 2 divisors, whose sum is σ = 221664121094. Its totient is φ = 221664121092.

The previous prime is 221664121051. The next prime is 221664121097. The reversal of 221664121093 is 390121466122.

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., 177395119489 + 44269001604 = 421183^2 + 210402^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221664121093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221664121097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110832060546 + 110832060547.

It is an arithmetic number, because the mean of its divisors is an integer number (110832060547).

Almost surely, 2^221664121093 is an apocalyptic number.

It is an amenable number.

221664121093 is a deficient number, since it is larger than the sum of its proper divisors (1).

221664121093 is an equidigital number, since it uses as much as digits as its factorization.

221664121093 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 37.

The spelling of 221664121093 in words is "two hundred twenty-one billion, six hundred sixty-four million, one hundred twenty-one thousand, ninety-three".