21161324 has 6 divisors (see below), whose sum is σ = 37032324. Its totient is φ = 10580660.

The previous prime is 21161323. The next prime is 21161377. The reversal of 21161324 is 42316112.

It is a junction number, because it is equal to n+sod(n) for n = 21161296 and 21161305.

It is not an unprimeable number, because it can be changed into a prime (21161321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2645162 + ... + 2645169.

It is an arithmetic number, because the mean of its divisors is an integer number (6172054).

Almost surely, 2^21161324 is an apocalyptic number.

It is an amenable number.

21161324 is a deficient number, since it is larger than the sum of its proper divisors (15871000).

21161324 is a wasteful number, since it uses less digits than its factorization.

21161324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5290335 (or 5290333 counting only the distinct ones).

The product of its digits is 288, while the sum is 20.

The square root of 21161324 is about 4600.1439107924. The cubic root of 21161324 is about 276.5970935203.

Adding to 21161324 its reverse (42316112), we get a palindrome (63477436).

The spelling of 21161324 in words is "twenty-one million, one hundred sixty-one thousand, three hundred twenty-four".