2158638 has 16 divisors (see below), whose sum is σ = 4362960. Its totient is φ = 711936.

The previous prime is 2158631. The next prime is 2158649. The reversal of 2158638 is 8368512.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 2158599 and 2158608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2158631) 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, 1273 + ... + 2436.

It is an arithmetic number, because the mean of its divisors is an integer number (272685).

2^2158638 is an apocalyptic number.

2158638 is an abundant number, since it is smaller than the sum of its proper divisors (2204322).

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

2158638 is a wasteful number, since it uses less digits than its factorization.

2158638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3811.

The product of its digits is 11520, while the sum is 33.

The square root of 2158638 is about 1469.2304107934. The cubic root of 2158638 is about 129.2389058740.

The spelling of 2158638 in words is "two million, one hundred fifty-eight thousand, six hundred thirty-eight".