2138656 has 48 divisors (see below), whose sum is σ = 4667544. Its totient is φ = 958464.

The previous prime is 2138629. The next prime is 2138657. The reversal of 2138656 is 6568312.

It can be written as a sum of positive squares in 4 ways, for example, as 1648656 + 490000 = 1284^2 + 700^2 .

It is not an unprimeable number, because it can be changed into a prime (2138657) 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, 22000 + ... + 22096.

2^2138656 is an apocalyptic number.

2138656 is a gapful number since it is divisible by the number (26) 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 2138656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2333772).

2138656 is an abundant number, since it is smaller than the sum of its proper divisors (2528888).

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

2138656 is a wasteful number, since it uses less digits than its factorization.

2138656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173 (or 165 counting only the distinct ones).

The product of its digits is 8640, while the sum is 31.

The square root of 2138656 is about 1462.4144419418. The cubic root of 2138656 is about 128.8388910758.

The spelling of 2138656 in words is "two million, one hundred thirty-eight thousand, six hundred fifty-six".