21000120999941 has 2 divisors, whose sum is σ = 21000120999942. Its totient is φ = 21000120999940.

The previous prime is 21000120999931. The next prime is 21000120999973. The reversal of 21000120999941 is 14999902100012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11357263962916 + 9642857037025 = 3370054^2 + 3105295^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000120999941 - 2¹⁰ = 21000120998917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21000120999901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500060499970 + 10500060499971.

It is an arithmetic number, because the mean of its divisors is an integer number (10500060499971).

Almost surely, 2^{21000120999941} is an apocalyptic number.

It is an amenable number.

21000120999941 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000120999941 is an equidigital number, since it uses as much as digits as its factorization.

21000120999941 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 104976, while the sum is 47.

The spelling of 21000120999941 in words is "twenty-one trillion, one hundred twenty million, nine hundred ninety-nine thousand, nine hundred forty-one".