2138406 has 16 divisors (see below), whose sum is σ = 4368384. Its totient is φ = 697544.

The previous prime is 2138401. The next prime is 2138407. The reversal of 2138406 is 6048312.

2138406 = 226² + 227² + ... + 261².

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2138401) 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 7 ways as a sum of consecutive naturals, for example, 3510 + ... + 4073.

It is an arithmetic number, because the mean of its divisors is an integer number (273024).

2^2138406 is an apocalyptic number.

2138406 is an abundant number, since it is smaller than the sum of its proper divisors (2229978).

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

2138406 is a wasteful number, since it uses less digits than its factorization.

2138406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7635.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 2138406 is about 1462.3289643579. The cubic root of 2138406 is about 128.8338706365.

The spelling of 2138406 in words is "two million, one hundred thirty-eight thousand, four hundred six".