21162830 has 16 divisors (see below), whose sum is σ = 41023584. Its totient is φ = 7813920.

The previous prime is 21162811. The next prime is 21162839. The reversal of 21162830 is 3826112.

It is a junction number, because it is equal to n+sod(n) for n = 21162796 and 21162805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21162839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 81266 + ... + 81525.

It is an arithmetic number, because the mean of its divisors is an integer number (2563974).

Almost surely, 2^21162830 is an apocalyptic number.

21162830 is a deficient number, since it is larger than the sum of its proper divisors (19860754).

21162830 is a wasteful number, since it uses less digits than its factorization.

21162830 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162811.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 21162830 is about 4600.3075984112. The cubic root of 21162830 is about 276.6036549456.

Adding to 21162830 its reverse (3826112), we get a palindrome (24988942).

The spelling of 21162830 in words is "twenty-one million, one hundred sixty-two thousand, eight hundred thirty".