3640521 has 8 divisors (see below), whose sum is σ = 4897440. Its totient is φ = 2405312.

The previous prime is 3640519. The next prime is 3640523. The reversal of 3640521 is 1250463.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (3640519) and next prime (3640523).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3640521 - 2¹ = 3640519 is a prime.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (3640523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5031 + ... + 5708.

It is an arithmetic number, because the mean of its divisors is an integer number (612180).

Almost surely, 2^3640521 is an apocalyptic number.

It is an amenable number.

3640521 is a deficient number, since it is larger than the sum of its proper divisors (1256919).

3640521 is a wasteful number, since it uses less digits than its factorization.

3640521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10855.

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 3640521 is about 1908.0149370484. The cubic root of 3640521 is about 153.8347724721.

Adding to 3640521 its reverse (1250463), we get a palindrome (4890984).

The spelling of 3640521 in words is "three million, six hundred forty thousand, five hundred twenty-one".