2181387 has 8 divisors (see below), whose sum is σ = 3132304. Its totient is φ = 1342368.

The previous prime is 2181379. The next prime is 2181419. The reversal of 2181387 is 7831812.

It is a happy number.

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

It is not a de Polignac number, because 2181387 - 2³ = 2181379 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181337) 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, 27928 + ... + 28005.

It is an arithmetic number, because the mean of its divisors is an integer number (391538).

2^2181387 is an apocalyptic number.

2181387 is a deficient number, since it is larger than the sum of its proper divisors (950917).

2181387 is a wasteful number, since it uses less digits than its factorization.

2181387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55949.

The product of its digits is 2688, while the sum is 30.

The square root of 2181387 is about 1476.9519288047. The cubic root of 2181387 is about 129.6913189082.

The spelling of 2181387 in words is "two million, one hundred eighty-one thousand, three hundred eighty-seven".