213724 has 24 divisors (see below), whose sum is σ = 453600. Its totient is φ = 86016.

The previous prime is 213721. The next prime is 213727. The reversal of 213724 is 427312.

213724 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (213721) and next prime (213727).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252 + ... + 700.

It is an arithmetic number, because the mean of its divisors is an integer number (18900).

2²¹³⁷²⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 213724, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (226800).

213724 is an abundant number, since it is smaller than the sum of its proper divisors (239876).

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

213724 is a wasteful number, since it uses less digits than its factorization.

213724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 477 (or 475 counting only the distinct ones).

The product of its digits is 336, while the sum is 19.

The square root of 213724 is about 462.3029309879. The cubic root of 213724 is about 59.7885147012.

The spelling of 213724 in words is "two hundred thirteen thousand, seven hundred twenty-four".