3521240521 has 4 divisors (see below), whose sum is σ = 3522486292. Its totient is φ = 3519994752.

The previous prime is 3521240519. The next prime is 3521240551. The reversal of 3521240521 is 1250421253.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1460080521 + 2061160000 = 38211^2 + 45400^2 .

It is a cyclic number.

It is not a de Polignac number, because 3521240521 - 2¹ = 3521240519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3521240501) 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, 618636 + ... + 624301.

It is an arithmetic number, because the mean of its divisors is an integer number (880621573).

Almost surely, 2^3521240521 is an apocalyptic number.

It is an amenable number.

3521240521 is a deficient number, since it is larger than the sum of its proper divisors (1245771).

3521240521 is a wasteful number, since it uses less digits than its factorization.

3521240521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1245770.

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 3521240521 is about 59340.0414644277. The cubic root of 3521240521 is about 1521.3596618917.

Adding to 3521240521 its reverse (1250421253), we get a palindrome (4771661774).

The spelling of 3521240521 in words is "three billion, five hundred twenty-one million, two hundred forty thousand, five hundred twenty-one".