21755421445007 has 2 divisors, whose sum is σ = 21755421445008. Its totient is φ = 21755421445006.

The previous prime is 21755421444989. The next prime is 21755421445013. The reversal of 21755421445007 is 70054412455712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21755421445007 - 2⁶ = 21755421444943 is a prime.

It is a super-3 number, since 3×21755421445007³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21755429445007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10877710722503 + 10877710722504.

It is an arithmetic number, because the mean of its divisors is an integer number (10877710722504).

Almost surely, 2^{21755421445007} is an apocalyptic number.

21755421445007 is a deficient number, since it is larger than the sum of its proper divisors (1).

21755421445007 is an equidigital number, since it uses as much as digits as its factorization.

21755421445007 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1568000, while the sum is 47.

The spelling of 21755421445007 in words is "twenty-one trillion, seven hundred fifty-five billion, four hundred twenty-one million, four hundred forty-five thousand, seven".