3213521 has 4 divisors (see below), whose sum is σ = 3261552. Its totient is φ = 3165492.

The previous prime is 3213499. The next prime is 3213559. The reversal of 3213521 is 1253123.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1253123 = 61 ⋅20543.

It is a cyclic number.

It is not a de Polignac number, because 3213521 - 2¹⁴ = 3197137 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3213521.

It is not an unprimeable number, because it can be changed into a prime (3213421) 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, 23915 + ... + 24048.

It is an arithmetic number, because the mean of its divisors is an integer number (815388).

Almost surely, 2^3213521 is an apocalyptic number.

It is an amenable number.

3213521 is a deficient number, since it is larger than the sum of its proper divisors (48031).

3213521 is an equidigital number, since it uses as much as digits as its factorization.

3213521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48030.

The product of its digits is 180, while the sum is 17.

The square root of 3213521 is about 1792.6296326905. The cubic root of 3213521 is about 147.5685174345.

Adding to 3213521 its reverse (1253123), we get a palindrome (4466644).

The spelling of 3213521 in words is "three million, two hundred thirteen thousand, five hundred twenty-one".