21131210941 has 2 divisors, whose sum is σ = 21131210942. Its totient is φ = 21131210940.

The previous prime is 21131210917. The next prime is 21131210983. The reversal of 21131210941 is 14901213112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15797976100 + 5333234841 = 125690^2 + 73029^2 .

It is a cyclic number.

It is not a de Polignac number, because 21131210941 - 2⁷ = 21131210813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21131210041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10565605470 + 10565605471.

It is an arithmetic number, because the mean of its divisors is an integer number (10565605471).

Almost surely, 2^21131210941 is an apocalyptic number.

It is an amenable number.

21131210941 is a deficient number, since it is larger than the sum of its proper divisors (1).

21131210941 is an equidigital number, since it uses as much as digits as its factorization.

21131210941 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 25.

The spelling of 21131210941 in words is "twenty-one billion, one hundred thirty-one million, two hundred ten thousand, nine hundred forty-one".