6647540 has 24 divisors (see below), whose sum is σ = 14008680. Its totient is φ = 2649728.

The previous prime is 6647521. The next prime is 6647551. The reversal of 6647540 is 457466.

It can be written as a sum of positive squares in 4 ways, for example, as 781456 + 5866084 = 884^2 + 2422^2 .

It is a junction number, because it is equal to n+sod(n) for n = 6647497 and 6647506.

It is a congruent number.

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, 9854 + ... + 10506.

It is an arithmetic number, because the mean of its divisors is an integer number (583695).

Almost surely, 2^6647540 is an apocalyptic number.

It is an amenable number.

6647540 is an abundant number, since it is smaller than the sum of its proper divisors (7361140).

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

6647540 is a wasteful number, since it uses less digits than its factorization.

6647540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1171 (or 1169 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 32.

The square root of 6647540 is about 2578.2823739847. The cubic root of 6647540 is about 188.0270445476.

The spelling of 6647540 in words is "six million, six hundred forty-seven thousand, five hundred forty".