2179987 has 4 divisors (see below), whose sum is σ = 2194576. Its totient is φ = 2165400.

The previous prime is 2179981. The next prime is 2179993. The reversal of 2179987 is 7899712.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (2179981) and next prime (2179993).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2179987 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2179981) 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, 7068 + ... + 7369.

It is an arithmetic number, because the mean of its divisors is an integer number (548644).

2^2179987 is an apocalyptic number.

2179987 is a deficient number, since it is larger than the sum of its proper divisors (14589).

2179987 is a wasteful number, since it uses less digits than its factorization.

2179987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14588.

The product of its digits is 63504, while the sum is 43.

The square root of 2179987 is about 1476.4779036613. The cubic root of 2179987 is about 129.6635679554.

It can be divided in two parts, 21 and 79987, that added together give a palindrome (80008).

The spelling of 2179987 in words is "two million, one hundred seventy-nine thousand, nine hundred eighty-seven".