21211432169 has 2 divisors, whose sum is σ = 21211432170. Its totient is φ = 21211432168.

The previous prime is 21211432133. The next prime is 21211432183. The reversal of 21211432169 is 96123411212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19821260944 + 1390171225 = 140788^2 + 37285^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21211432169 is a prime.

It is a super-2 number, since 2×21211432169² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21211432469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605716084 + 10605716085.

It is an arithmetic number, because the mean of its divisors is an integer number (10605716085).

Almost surely, 2^21211432169 is an apocalyptic number.

It is an amenable number.

21211432169 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211432169 is an equidigital number, since it uses as much as digits as its factorization.

21211432169 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5184, while the sum is 32.

The spelling of 21211432169 in words is "twenty-one billion, two hundred eleven million, four hundred thirty-two thousand, one hundred sixty-nine".