2121686 has 8 divisors (see below), whose sum is σ = 3637200. Its totient is φ = 909288.

The previous prime is 2121683. The next prime is 2121737. The reversal of 2121686 is 6861212.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121683) 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, 75761 + ... + 75788.

It is an arithmetic number, because the mean of its divisors is an integer number (454650).

2^2121686 is an apocalyptic number.

2121686 is a deficient number, since it is larger than the sum of its proper divisors (1515514).

2121686 is a wasteful number, since it uses less digits than its factorization.

2121686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151558.

The product of its digits is 1152, while the sum is 26.

The square root of 2121686 is about 1456.6008375667. The cubic root of 2121686 is about 128.4972116056.

Adding to 2121686 its reverse (6861212), we get a palindrome (8982898).

The spelling of 2121686 in words is "two million, one hundred twenty-one thousand, six hundred eighty-six".