3521440 has 48 divisors (see below), whose sum is σ = 8964648. Its totient is φ = 1299456.

The previous prime is 3521437. The next prime is 3521473. The reversal of 3521440 is 441253.

3521440 = 200² + 201² + ... + 264².

It can be written as a sum of positive squares in 4 ways, for example, as 1993744 + 1527696 = 1412^2 + 1236^2 .

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, 1234 + ... + 2926.

Almost surely, 2^3521440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3521440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4482324).

3521440 is an abundant number, since it is smaller than the sum of its proper divisors (5443208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3521440 is a wasteful number, since it uses less digits than its factorization.

3521440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1721 (or 1713 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 3521440 is about 1876.5500259785. The cubic root of 3521440 is about 152.1388389795.

Adding to 3521440 its reverse (441253), we get a palindrome (3962693).

The spelling of 3521440 in words is "three million, five hundred twenty-one thousand, four hundred forty".