20921041 has 2 divisors, whose sum is σ = 20921042. Its totient is φ = 20921040.

The previous prime is 20921027. The next prime is 20921059. The reversal of 20921041 is 14012902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18671041 + 2250000 = 4321^2 + 1500^2 .

It is a cyclic number.

It is not a de Polignac number, because 20921041 - 2⁵ = 20921009 is a prime.

It is not a weakly prime, because it can be changed into another prime (20921081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10460520 + 10460521.

It is an arithmetic number, because the mean of its divisors is an integer number (10460521).

Almost surely, 2^20921041 is an apocalyptic number.

It is an amenable number.

20921041 is a deficient number, since it is larger than the sum of its proper divisors (1).

20921041 is an equidigital number, since it uses as much as digits as its factorization.

20921041 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 20921041 is about 4573.9524483755. The cubic root of 20921041 is about 275.5462025733.

Adding to 20921041 its reverse (14012902), we get a palindrome (34933943).

The spelling of 20921041 in words is "twenty million, nine hundred twenty-one thousand, forty-one".