2181138 has 8 divisors (see below), whose sum is σ = 4362288. Its totient is φ = 727044.

The previous prime is 2181131. The next prime is 2181139. The reversal of 2181138 is 8311812.

It is a sphenic number, since it is the product of 3 distinct primes.

2181138 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (2181131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 181756 + ... + 181767.

It is an arithmetic number, because the mean of its divisors is an integer number (545286).

2^2181138 is an apocalyptic number.

2181138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

2181138 is a wasteful number, since it uses less digits than its factorization.

2181138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363528.

The product of its digits is 384, while the sum is 24.

The square root of 2181138 is about 1476.8676311708. The cubic root of 2181138 is about 129.6863840713.

The spelling of 2181138 in words is "two million, one hundred eighty-one thousand, one hundred thirty-eight".