20920841 has 2 divisors, whose sum is σ = 20920842. Its totient is φ = 20920840.

The previous prime is 20920819. The next prime is 20920847. The reversal of 20920841 is 14802902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16168441 + 4752400 = 4021^2 + 2180^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20920841 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20920841.

It is not a weakly prime, because it can be changed into another prime (20920847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10460420 + 10460421.

It is an arithmetic number, because the mean of its divisors is an integer number (10460421).

Almost surely, 2^20920841 is an apocalyptic number.

It is an amenable number.

20920841 is a deficient number, since it is larger than the sum of its proper divisors (1).

20920841 is an equidigital number, since it uses as much as digits as its factorization.

20920841 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 20920841 is about 4573.9305853937. The cubic root of 20920841 is about 275.5453245192.

The spelling of 20920841 in words is "twenty million, nine hundred twenty thousand, eight hundred forty-one".