101906221 has 2 divisors, whose sum is σ = 101906222. Its totient is φ = 101906220.

The previous prime is 101906209. The next prime is 101906237. The reversal of 101906221 is 122609101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 99301225 + 2604996 = 9965^2 + 1614^2 .

It is a cyclic number.

It is not a de Polignac number, because 101906221 - 2⁷ = 101906093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 101906192 and 101906201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101906521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50953110 + 50953111.

It is an arithmetic number, because the mean of its divisors is an integer number (50953111).

Almost surely, 2^101906221 is an apocalyptic number.

It is an amenable number.

101906221 is a deficient number, since it is larger than the sum of its proper divisors (1).

101906221 is an equidigital number, since it uses as much as digits as its factorization.

101906221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 101906221 is about 10094.8611184107. The cubic root of 101906221 is about 467.0896373231.

The spelling of 101906221 in words is "one hundred one million, nine hundred six thousand, two hundred twenty-one".