213528 has 64 divisors (see below), whose sum is σ = 645120. Its totient is φ = 57600.

The previous prime is 213523. The next prime is 213533. The reversal of 213528 is 825312.

It is an interprime number because it is at equal distance from previous prime (213523) and next prime (213533).

It is a hoax number, since the sum of its digits (21) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213523) by changing a digit.

213528 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5188 + ... + 5228.

It is an arithmetic number, because the mean of its divisors is an integer number (10080).

213528 is a Friedman number, since it can be written as 82*(51^2+3), using all its digits and the basic arithmetic operations.

2²¹³⁵²⁸ is an apocalyptic number.

213528 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 213528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (322560).

213528 is an abundant number, since it is smaller than the sum of its proper divisors (431592).

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

213528 is a wasteful number, since it uses less digits than its factorization.

213528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88 (or 84 counting only the distinct ones).

The product of its digits is 480, while the sum is 21.

The square root of 213528 is about 462.0909001484. The cubic root of 213528 is about 59.7702323480.

It can be divided in two parts, 213 and 528, that added together give a triangular number (741 = T₃₈).

The spelling of 213528 in words is "two hundred thirteen thousand, five hundred twenty-eight".