19724 has 6 divisors (see below), whose sum is σ = 34524. Its totient is φ = 9860.

The previous prime is 19717. The next prime is 19727. The reversal of 19724 is 42791.

It is a plaindrome in base 5 and base 7.

It is a self number, because there is not a number n which added to its sum of digits gives 19724.

It is not an unprimeable number, because it can be changed into a prime (19727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2462 + ... + 2469.

It is an arithmetic number, because the mean of its divisors is an integer number (5754).

2¹⁹⁷²⁴ is an apocalyptic number.

It is an amenable number.

19724 is a deficient number, since it is larger than the sum of its proper divisors (14800).

19724 is a wasteful number, since it uses less digits than its factorization.

19724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4935 (or 4933 counting only the distinct ones).

The product of its digits is 504, while the sum is 23.

The square root of 19724 is about 140.4421589125. The cubic root of 19724 is about 27.0187341404.

Subtracting from 19724 its sum of digits (23), we obtain a triangular number (19701 = T₁₉₈).

The spelling of 19724 in words is "nineteen thousand, seven hundred twenty-four".