213128 has 8 divisors (see below), whose sum is σ = 399630. Its totient is φ = 106560.

The previous prime is 213119. The next prime is 213131. The reversal of 213128 is 821312.

It can be written as a sum of positive squares in only one way, i.e., 209764 + 3364 = 458^2 + 58^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an Ulam number.

It is an unprimeable number.

213128 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 as a sum of consecutive naturals, namely, 13313 + ... + 13328.

2²¹³¹²⁸ is an apocalyptic number.

It is an amenable number.

213128 is a deficient number, since it is larger than the sum of its proper divisors (186502).

213128 is a wasteful number, since it uses less digits than its factorization.

213128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26647 (or 26643 counting only the distinct ones).

The product of its digits is 96, while the sum is 17.

The square root of 213128 is about 461.6578819862. The cubic root of 213128 is about 59.7328866800.

The spelling of 213128 in words is "two hundred thirteen thousand, one hundred twenty-eight".