2138 has 4 divisors (see below), whose sum is σ = 3210. Its totient is φ = 1068.

The previous prime is 2137. The next prime is 2141. The reversal of 2138 is 8312.

2138 is nontrivially palindromic in base 5 and base 14.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1849 + 289 = 43^2 + 17^2 .

It is a d-powerful number, because it can be written as 2¹¹ + 3⁴ + 1 + 8 .

2138 is an undulating number in base 14.

It is a nialpdrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (2131) 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 as a sum of consecutive naturals, namely, 533 + ... + 536.

2²¹³⁸ is an apocalyptic number.

2138 is a deficient number, since it is larger than the sum of its proper divisors (1072).

2138 is a wasteful number, since it uses less digits than its factorization.

2138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1071.

The product of its digits is 48, while the sum is 14.

The square root of 2138 is about 46.2385120868. The cubic root of 2138 is about 12.8825716609.

It can be divided in two parts, 2 and 138, that multiplied together give a triangular number (276 = T₂₃).

The spelling of 2138 in words is "two thousand, one hundred thirty-eight".