21131143009 has 2 divisors, whose sum is σ = 21131143010. Its totient is φ = 21131143008.

The previous prime is 21131142943. The next prime is 21131143013. The reversal of 21131143009 is 90034113112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17856442384 + 3274700625 = 133628^2 + 57225^2 .

It is a cyclic number.

It is not a de Polignac number, because 21131143009 - 2²⁷ = 20996925281 is a prime.

It is not a weakly prime, because it can be changed into another prime (21131143069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10565571504 + 10565571505.

It is an arithmetic number, because the mean of its divisors is an integer number (10565571505).

Almost surely, 2^21131143009 is an apocalyptic number.

It is an amenable number.

21131143009 is a deficient number, since it is larger than the sum of its proper divisors (1).

21131143009 is an equidigital number, since it uses as much as digits as its factorization.

21131143009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 25.

The spelling of 21131143009 in words is "twenty-one billion, one hundred thirty-one million, one hundred forty-three thousand, nine".