2121001 has 4 divisors (see below), whose sum is σ = 2136400. Its totient is φ = 2105604.

The previous prime is 2120981. The next prime is 2121011. The reversal of 2121001 is 1001212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2121001 - 2¹⁹ = 1596713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2121011) 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, 7491 + ... + 7768.

It is an arithmetic number, because the mean of its divisors is an integer number (534100).

2^2121001 is an apocalyptic number.

It is an amenable number.

2121001 is a deficient number, since it is larger than the sum of its proper divisors (15399).

2121001 is a wasteful number, since it uses less digits than its factorization.

2121001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15398.

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 2121001 is about 1456.3656821005. The cubic root of 2121001 is about 128.4833813994.

Adding to 2121001 its reverse (1001212), we get a palindrome (3122213).

It can be divided in two parts, 212 and 1001, that multiplied together give a palindrome (212212).

The spelling of 2121001 in words is "two million, one hundred twenty-one thousand, one".