106815221 has 2 divisors, whose sum is σ = 106815222. Its totient is φ = 106815220.

The previous prime is 106815179. The next prime is 106815229. The reversal of 106815221 is 122518601.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87796900 + 19018321 = 9370^2 + 4361^2 .

It is a cyclic number.

It is not a de Polignac number, because 106815221 - 2⁶ = 106815157 is a prime.

It is a super-2 number, since 2×106815221² = 22818982874557682, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (106815229) 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, 53407610 + 53407611.

It is an arithmetic number, because the mean of its divisors is an integer number (53407611).

Almost surely, 2^106815221 is an apocalyptic number.

It is an amenable number.

106815221 is a deficient number, since it is larger than the sum of its proper divisors (1).

106815221 is an equidigital number, since it uses as much as digits as its factorization.

106815221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 26.

The square root of 106815221 is about 10335.1449433474. The cubic root of 106815221 is about 474.4725017681.

The spelling of 106815221 in words is "one hundred six million, eight hundred fifteen thousand, two hundred twenty-one".