213138 has 16 divisors (see below), whose sum is σ = 473760. Its totient is φ = 71028.

The previous prime is 213133. The next prime is 213139. The reversal of 213138 is 831312.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a self number, because there is not a number n which added to its sum of digits gives 213138.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 213138.

It is not an unprimeable number, because it can be changed into a prime (213131) 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, 1920 + ... + 2027.

It is an arithmetic number, because the mean of its divisors is an integer number (29610).

2²¹³¹³⁸ is an apocalyptic number.

213138 is an abundant number, since it is smaller than the sum of its proper divisors (260622).

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

213138 is a wasteful number, since it uses less digits than its factorization.

213138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3958 (or 3952 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 213138 is about 461.6687123902. The cubic root of 213138 is about 59.7338208909.

It can be divided in two parts, 21313 and 8, that added together give a triangular number (21321 = T₂₀₆).

The spelling of 213138 in words is "two hundred thirteen thousand, one hundred thirty-eight".