213081 has 12 divisors (see below), whose sum is σ = 312816. Its totient is φ = 128920.

The previous prime is 213079. The next prime is 213091. The reversal of 213081 is 180312.

It is a happy number.

It is not a de Polignac number, because 213081 - 2¹ = 213079 is a prime.

It is a super-2 number, since 2×213081² = 90807025122, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 213081.

It is not an unprimeable number, because it can be changed into a prime (213091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 70 + ... + 656.

It is an arithmetic number, because the mean of its divisors is an integer number (26068).

2²¹³⁰⁸¹ is an apocalyptic number.

It is an amenable number.

213081 is a deficient number, since it is larger than the sum of its proper divisors (99735).

213081 is a wasteful number, since it uses less digits than its factorization.

213081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 612 (or 601 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 213081 is about 461.6069756839. The cubic root of 213081 is about 59.7284954971.

Adding to 213081 its reverse (180312), we get a palindrome (393393).

It can be divided in two parts, 2130 and 81, that added together give a triangular number (2211 = T₆₆).

The spelling of 213081 in words is "two hundred thirteen thousand, eighty-one".