20910101 has 2 divisors, whose sum is σ = 20910102. Its totient is φ = 20910100.

The previous prime is 20910067. The next prime is 20910103. The reversal of 20910101 is 10101902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18054001 + 2856100 = 4249^2 + 1690^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20910101 is a prime.

Together with 20910103, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20910103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10455050 + 10455051.

It is an arithmetic number, because the mean of its divisors is an integer number (10455051).

Almost surely, 2^20910101 is an apocalyptic number.

It is an amenable number.

20910101 is a deficient number, since it is larger than the sum of its proper divisors (1).

20910101 is an equidigital number, since it uses as much as digits as its factorization.

20910101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 20910101 is about 4572.7563897501. The cubic root of 20910101 is about 275.4981647940.

The spelling of 20910101 in words is "twenty million, nine hundred ten thousand, one hundred one".