21955490707243 has 2 divisors, whose sum is σ = 21955490707244. Its totient is φ = 21955490707242.

The previous prime is 21955490707229. The next prime is 21955490707279. The reversal of 21955490707243 is 34270709455912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21955490707243 - 2⁴¹ = 19756467451691 is a prime.

It is a super-2 number, since 2×21955490707243² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21955490707223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10977745353621 + 10977745353622.

It is an arithmetic number, because the mean of its divisors is an integer number (10977745353622).

Almost surely, 2^{21955490707243} is an apocalyptic number.

21955490707243 is a deficient number, since it is larger than the sum of its proper divisors (1).

21955490707243 is an equidigital number, since it uses as much as digits as its factorization.

21955490707243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19051200, while the sum is 58.

The spelling of 21955490707243 in words is "twenty-one trillion, nine hundred fifty-five billion, four hundred ninety million, seven hundred seven thousand, two hundred forty-three".