21124142 has 8 divisors (see below), whose sum is σ = 34123656. Its totient is φ = 9749592.

The previous prime is 21124141. The next prime is 21124163. The reversal of 21124142 is 24142112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21124142.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21124141) 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, 406208 + ... + 406259.

It is an arithmetic number, because the mean of its divisors is an integer number (4265457).

Almost surely, 2^21124142 is an apocalyptic number.

21124142 is a deficient number, since it is larger than the sum of its proper divisors (12999514).

21124142 is a wasteful number, since it uses less digits than its factorization.

21124142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812482.

The product of its digits is 128, while the sum is 17.

The square root of 21124142 is about 4596.1007386697. The cubic root of 21124142 is about 276.4349980780.

Adding to 21124142 its reverse (24142112), we get a palindrome (45266254).

The spelling of 21124142 in words is "twenty-one million, one hundred twenty-four thousand, one hundred forty-two".