21010032161 has 2 divisors, whose sum is σ = 21010032162. Its totient is φ = 21010032160.

The previous prime is 21010032091. The next prime is 21010032191. The reversal of 21010032161 is 16123001012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16686180625 + 4323851536 = 129175^2 + 65756^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010032161 - 2²⁶ = 20942923297 is a prime.

It is not a weakly prime, because it can be changed into another prime (21010032191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505016080 + 10505016081.

It is an arithmetic number, because the mean of its divisors is an integer number (10505016081).

Almost surely, 2^21010032161 is an apocalyptic number.

It is an amenable number.

21010032161 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010032161 is an equidigital number, since it uses as much as digits as its factorization.

21010032161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21010032161 its reverse (16123001012), we get a palindrome (37133033173).

The spelling of 21010032161 in words is "twenty-one billion, ten million, thirty-two thousand, one hundred sixty-one".