6660621 has 24 divisors (see below), whose sum is σ = 11051040. Its totient is φ = 3823200.

The previous prime is 6660613. The next prime is 6660649. The reversal of 6660621 is 1260666.

It is not a de Polignac number, because 6660621 - 2³ = 6660613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6660601) 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, 111 + ... + 3651.

It is an arithmetic number, because the mean of its divisors is an integer number (460460).

Almost surely, 2^6660621 is an apocalyptic number.

It is an amenable number.

6660621 is a deficient number, since it is larger than the sum of its proper divisors (4390419).

6660621 is a wasteful number, since it uses less digits than its factorization.

6660621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3577 (or 3574 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 6660621 is about 2580.8178936143. The cubic root of 6660621 is about 188.1502966685.

The spelling of 6660621 in words is "six million, six hundred sixty thousand, six hundred twenty-one".