6780661 has 8 divisors (see below), whose sum is σ = 7133184. Its totient is φ = 6436560.

The previous prime is 6780629. The next prime is 6780679. The reversal of 6780661 is 1660876.

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 6780661 - 2⁵ = 6780629 is a prime.

It is a Duffinian number.

6780661 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6780611) 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, 421 + ... + 3706.

It is an arithmetic number, because the mean of its divisors is an integer number (891648).

Almost surely, 2^6780661 is an apocalyptic number.

It is an amenable number.

6780661 is a deficient number, since it is larger than the sum of its proper divisors (352523).

6780661 is a wasteful number, since it uses less digits than its factorization.

6780661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4211.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 6780661 is about 2603.9702379252. The cubic root of 6780661 is about 189.2738767081.

The spelling of 6780661 in words is "six million, seven hundred eighty thousand, six hundred sixty-one".