20012261 has 2 divisors, whose sum is σ = 20012262. Its totient is φ = 20012260.

The previous prime is 20012219. The next prime is 20012287. The reversal of 20012261 is 16221002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15952036 + 4060225 = 3994^2 + 2015^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20012261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20012561) 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, 10006130 + 10006131.

It is an arithmetic number, because the mean of its divisors is an integer number (10006131).

Almost surely, 2^20012261 is an apocalyptic number.

It is an amenable number.

20012261 is a deficient number, since it is larger than the sum of its proper divisors (1).

20012261 is an equidigital number, since it uses as much as digits as its factorization.

20012261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 20012261 is about 4473.5065664420. The cubic root of 20012261 is about 271.4972194522.

Adding to 20012261 its reverse (16221002), we get a palindrome (36233263).

The spelling of 20012261 in words is "twenty million, twelve thousand, two hundred sixty-one".