106721 has 2 divisors, whose sum is σ = 106722.
Its totient is φ = 106720.
The previous prime is 106703. The next prime is 106727. The reversal of 106721 is 127601.
It is a happy number.
106721 is nontrivially palindromic in base 12.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 96721 + 10000 = 311^2 + 100^2
It is an emirp because it is prime and its reverse (127601) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 106721 - 26 = 106657 is a prime.
It is a super-2 number, since 2×1067212 = 22778743682, which contains 22 as substring.
It is a self number, because there is not a number n which added to its sum of digits gives 106721.
It is not a weakly prime, because it can be changed into another prime (106727) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53360 + 53361.
It is an arithmetic number, because the mean of its divisors is an integer number (53361).
2106721 is an apocalyptic number.
It is an amenable number.
106721 is a deficient number, since it is larger than the sum of its proper divisors (1).
106721 is an equidigital number, since it uses as much as digits as its factorization.
106721 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 84, while the sum is 17.
The square root of 106721 is about 326.6818023704.
The cubic root of 106721 is about 47.4332951043.
The spelling of 106721 in words is "one hundred six thousand, seven hundred twenty-one".