21836124 has 18 divisors (see below), whose sum is σ = 55196960. Its totient is φ = 7278696.

The previous prime is 21836123. The next prime is 21836147. The reversal of 21836124 is 42163812.

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×21836124² = 953632622686752, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21836123) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 303244 + ... + 303315.

Almost surely, 2^21836124 is an apocalyptic number.

It is an amenable number.

21836124 is an abundant number, since it is smaller than the sum of its proper divisors (33360836).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21836124 is a wasteful number, since it uses less digits than its factorization.

21836124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 606569 (or 606564 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 21836124 is about 4672.9138661011. The cubic root of 21836124 is about 279.5064605101.

Adding to 21836124 its reverse (42163812), we get a palindrome (63999936).

The spelling of 21836124 in words is "twenty-one million, eight hundred thirty-six thousand, one hundred twenty-four".