21045124 has 12 divisors (see below), whose sum is σ = 36895824. Its totient is φ = 10503464.

The previous prime is 21045109. The next prime is 21045127. The reversal of 21045124 is 42154012.

It is not an unprimeable number, because it can be changed into a prime (21045127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2134 + ... + 6829.

It is an arithmetic number, because the mean of its divisors is an integer number (3074652).

Almost surely, 2^21045124 is an apocalyptic number.

It is an amenable number.

21045124 is a deficient number, since it is larger than the sum of its proper divisors (15850700).

21045124 is a wasteful number, since it uses less digits than its factorization.

21045124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9554 (or 9552 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 21045124 is about 4587.4964850123. The cubic root of 21045124 is about 276.0898853075.

Adding to 21045124 its reverse (42154012), we get a palindrome (63199136).

The spelling of 21045124 in words is "twenty-one million, forty-five thousand, one hundred twenty-four".