216721869438001 has 2 divisors, whose sum is σ = 216721869438002. Its totient is φ = 216721869438000.

The previous prime is 216721869437963. The next prime is 216721869438047. The reversal of 216721869438001 is 100834968127612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 128761761960976 + 87960107477025 = 11347324^2 + 9378705^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216721869438001 is a prime.

It is not a weakly prime, because it can be changed into another prime (216721869438091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108360934719000 + 108360934719001.

It is an arithmetic number, because the mean of its divisors is an integer number (108360934719001).

Almost surely, 2^{216721869438001} is an apocalyptic number.

It is an amenable number.

216721869438001 is a deficient number, since it is larger than the sum of its proper divisors (1).

216721869438001 is an equidigital number, since it uses as much as digits as its factorization.

216721869438001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6967296, while the sum is 58.

The spelling of 216721869438001 in words is "two hundred sixteen trillion, seven hundred twenty-one billion, eight hundred sixty-nine million, four hundred thirty-eight thousand, one".