3642521 has 4 divisors (see below), whose sum is σ = 3646500. Its totient is φ = 3638544.

The previous prime is 3642497. The next prime is 3642559. The reversal of 3642521 is 1252463.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1252463 = 179 ⋅6997.

It can be written as a sum of positive squares in 2 ways, for example, as 1792921 + 1849600 = 1339^2 + 1360^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3642521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3642571) 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, 155 + ... + 2703.

It is an arithmetic number, because the mean of its divisors is an integer number (911625).

Almost surely, 2^3642521 is an apocalyptic number.

It is an amenable number.

3642521 is a deficient number, since it is larger than the sum of its proper divisors (3979).

3642521 is a wasteful number, since it uses less digits than its factorization.

3642521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3978.

The product of its digits is 1440, while the sum is 23.

The square root of 3642521 is about 1908.5389699977. The cubic root of 3642521 is about 153.8629381496.

Adding to 3642521 its reverse (1252463), we get a palindrome (4894984).

The spelling of 3642521 in words is "three million, six hundred forty-two thousand, five hundred twenty-one".