21592161 has 6 divisors (see below), whose sum is σ = 31188690. Its totient is φ = 14394768.

The previous prime is 21592141. The next prime is 21592163. The reversal of 21592161 is 16129512.

It can be written as a sum of positive squares in only one way, i.e., 17766225 + 3825936 = 4215^2 + 1956^2 .

It is not a de Polignac number, because 21592161 - 2¹¹ = 21590113 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21592163) 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 5 ways as a sum of consecutive naturals, for example, 1199556 + ... + 1199573.

It is an arithmetic number, because the mean of its divisors is an integer number (5198115).

Almost surely, 2^21592161 is an apocalyptic number.

It is an amenable number.

21592161 is a deficient number, since it is larger than the sum of its proper divisors (9596529).

21592161 is a wasteful number, since it uses less digits than its factorization.

21592161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2399135 (or 2399132 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 21592161 is about 4646.7365967956. The cubic root of 21592161 is about 278.4616357414.

The spelling of 21592161 in words is "twenty-one million, five hundred ninety-two thousand, one hundred sixty-one".