7640521 has 12 divisors (see below), whose sum is σ = 8942160. Its totient is φ = 6509160.

The previous prime is 7640519. The next prime is 7640579. The reversal of 7640521 is 1250467.

It is not a de Polignac number, because 7640521 - 2¹ = 7640519 is a prime.

It is a super-2 number, since 2×7640521² = 116755122302882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7640221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9970 + ... + 10708.

It is an arithmetic number, because the mean of its divisors is an integer number (745180).

Almost surely, 2^7640521 is an apocalyptic number.

It is an amenable number.

7640521 is a deficient number, since it is larger than the sum of its proper divisors (1301639).

7640521 is a wasteful number, since it uses less digits than its factorization.

7640521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 964 (or 957 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 7640521 is about 2764.1492362027. The cubic root of 7640521 is about 196.9583169989.

Adding to 7640521 its reverse (1250467), we get a palindrome (8890988).

The spelling of 7640521 in words is "seven million, six hundred forty thousand, five hundred twenty-one".