3521520 has 120 divisors (see below), whose sum is σ = 12167376. Its totient is φ = 912384.

The previous prime is 3521519. The next prime is 3521527. The reversal of 3521520 is 251253.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×3521520² = 24802206220800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 3521493 and 3521502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3521527) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 48204 + ... + 48276.

Almost surely, 2^3521520 is an apocalyptic number.

3521520 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3521520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6083688).

3521520 is an abundant number, since it is smaller than the sum of its proper divisors (8645856).

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

3521520 is a wasteful number, since it uses less digits than its factorization.

3521520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 18.

The square root of 3521520 is about 1876.5713415695. The cubic root of 3521520 is about 152.1399910664.

Adding to 3521520 its reverse (251253), we get a palindrome (3772773).

The spelling of 3521520 in words is "three million, five hundred twenty-one thousand, five hundred twenty".