2123521 has 8 divisors (see below), whose sum is σ = 2346624. Its totient is φ = 1911360.

The previous prime is 2123491. The next prime is 2123557. The reversal of 2123521 is 1253212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2123521 is a prime.

It is a Duffinian number.

2123521 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 2123495 and 2123504.

It is not an unprimeable number, because it can be changed into a prime (2123581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2325 + ... + 3106.

It is an arithmetic number, because the mean of its divisors is an integer number (293328).

2^2123521 is an apocalyptic number.

It is an amenable number.

2123521 is a deficient number, since it is larger than the sum of its proper divisors (223103).

2123521 is a wasteful number, since it uses less digits than its factorization.

2123521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5471.

The product of its digits is 120, while the sum is 16.

The square root of 2123521 is about 1457.2305925968. The cubic root of 2123521 is about 128.5342457440.

Adding to 2123521 its reverse (1253212), we get a palindrome (3376733).

The spelling of 2123521 in words is "two million, one hundred twenty-three thousand, five hundred twenty-one".