2121005 has 8 divisors (see below), whose sum is σ = 2695032. Its totient is φ = 1596928.

The previous prime is 2120981. The next prime is 2121011. The reversal of 2121005 is 5001212.

It can be written as a sum of positive squares in 4 ways, for example, as 649636 + 1471369 = 806^2 + 1213^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 2121005 - 2⁶ = 2120941 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12392 + ... + 12561.

It is an arithmetic number, because the mean of its divisors is an integer number (336879).

2^2121005 is an apocalyptic number.

It is an amenable number.

2121005 is a deficient number, since it is larger than the sum of its proper divisors (574027).

2121005 is a wasteful number, since it uses less digits than its factorization.

2121005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24975.

The product of its (nonzero) digits is 20, while the sum is 11.

The square root of 2121005 is about 1456.3670553813. The cubic root of 2121005 is about 128.4834621684.

Adding to 2121005 its reverse (5001212), we get a palindrome (7122217).

The spelling of 2121005 in words is "two million, one hundred twenty-one thousand, five".