21213602001161 has 2 divisors, whose sum is σ = 21213602001162. Its totient is φ = 21213602001160.

The previous prime is 21213602001061. The next prime is 21213602001211. The reversal of 21213602001161 is 16110020631212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15157356630025 + 6056245371136 = 3893245^2 + 2460944^2 .

It is a cyclic number.

It is not a de Polignac number, because 21213602001161 - 2¹⁰ = 21213602000137 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21213602001161.

It is not a weakly prime, because it can be changed into another prime (21213602001061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606801000580 + 10606801000581.

It is an arithmetic number, because the mean of its divisors is an integer number (10606801000581).

Almost surely, 2^{21213602001161} is an apocalyptic number.

It is an amenable number.

21213602001161 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213602001161 is an equidigital number, since it uses as much as digits as its factorization.

21213602001161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

Adding to 21213602001161 its reverse (16110020631212), we get a palindrome (37323622632373).

The spelling of 21213602001161 in words is "twenty-one trillion, two hundred thirteen billion, six hundred two million, one thousand, one hundred sixty-one".