21163204161 has 12 divisors (see below), whose sum is σ = 33348079440. Its totient is φ = 12826184280.

The previous prime is 21163204159. The next prime is 21163204163. The reversal of 21163204161 is 16140236112.

It is a happy number.

21163204161 is a `hidden beast` number, since 2 + 11 + 632 + 0 + 4 + 16 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (21163204159) and next prime (21163204163).

It is not a de Polignac number, because 21163204161 - 2¹ = 21163204159 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21163204163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 106884771 + ... + 106884968.

It is an arithmetic number, because the mean of its divisors is an integer number (2779006620).

Almost surely, 2^21163204161 is an apocalyptic number.

It is an amenable number.

21163204161 is a deficient number, since it is larger than the sum of its proper divisors (12184875279).

21163204161 is a wasteful number, since it uses less digits than its factorization.

21163204161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213769756 (or 213769753 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The spelling of 21163204161 in words is "twenty-one billion, one hundred sixty-three million, two hundred four thousand, one hundred sixty-one".