21713124 has 24 divisors (see below), whose sum is σ = 53331040. Its totient is φ = 6856704.

The previous prime is 21713099. The next prime is 21713129. The reversal of 21713124 is 42131712.

It is a self number, because there is not a number n which added to its sum of digits gives 21713124.

It is not an unprimeable number, because it can be changed into a prime (21713129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47389 + ... + 47844.

Almost surely, 2^21713124 is an apocalyptic number.

It is an amenable number.

21713124 is an abundant number, since it is smaller than the sum of its proper divisors (31617916).

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

21713124 is a wasteful number, since it uses less digits than its factorization.

21713124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95259 (or 95257 counting only the distinct ones).

The product of its digits is 336, while the sum is 21.

The square root of 21713124 is about 4659.7343271908. The cubic root of 21713124 is about 278.9806643760.

Adding to 21713124 its reverse (42131712), we get a palindrome (63844836).

The spelling of 21713124 in words is "twenty-one million, seven hundred thirteen thousand, one hundred twenty-four".