213520 has 40 divisors (see below), whose sum is σ = 528984. Its totient is φ = 79872.

The previous prime is 213491. The next prime is 213523. The reversal of 213520 is 25312.

213520 = T₂₄ + T₂₅ + ... + T₁₀₈.

It can be written as a sum of positive squares in 4 ways, for example, as 26896 + 186624 = 164^2 + 432^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 213520.

It is a congruent number.

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

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1282 + ... + 1438.

2²¹³⁵²⁰ is an apocalyptic number.

213520 is a gapful number since it is divisible by the number (20) 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 213520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (264492).

213520 is an abundant number, since it is smaller than the sum of its proper divisors (315464).

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

213520 is a wasteful number, since it uses less digits than its factorization.

213520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187 (or 181 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 213520 is about 462.0822437619. The cubic root of 213520 is about 59.7694858919.

Adding to 213520 its reverse (25312), we get a palindrome (238832).

It can be divided in two parts, 21 and 3520, that multiplied together give a triangular number (73920 = T₃₈₄).

The spelling of 213520 in words is "two hundred thirteen thousand, five hundred twenty".