21367161 has 24 divisors (see below), whose sum is σ = 32535360. Its totient is φ = 13486176.

The previous prime is 21367139. The next prime is 21367163. The reversal of 21367161 is 16176312.

It is not a de Polignac number, because 21367161 - 2¹⁹ = 20842873 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21367163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22090 + ... + 23036.

It is an arithmetic number, because the mean of its divisors is an integer number (1355640).

Almost surely, 2^21367161 is an apocalyptic number.

It is an amenable number.

21367161 is a deficient number, since it is larger than the sum of its proper divisors (11168199).

21367161 is a wasteful number, since it uses less digits than its factorization.

21367161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1085 (or 1082 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 21367161 is about 4622.4626553386. The cubic root of 21367161 is about 277.4910247889.

It can be divided in two parts, 21367 and 161, that added together give a triangular number (21528 = T₂₀₇).

The spelling of 21367161 in words is "twenty-one million, three hundred sixty-seven thousand, one hundred sixty-one".