6620778 has 56 divisors (see below), whose sum is σ = 15739200. Its totient is φ = 2082024.

The previous prime is 6620777. The next prime is 6620791. The reversal of 6620778 is 8770266.

It is not an unprimeable number, because it can be changed into a prime (6620771) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 27583 + ... + 27821.

Almost surely, 2^6620778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6620778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7869600).

6620778 is an abundant number, since it is smaller than the sum of its proper divisors (9118422).

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

6620778 is a wasteful number, since it uses less digits than its factorization.

6620778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278 (or 263 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 6620778 is about 2573.0872507554. The cubic root of 6620778 is about 187.7743822807.

The spelling of 6620778 in words is "six million, six hundred twenty thousand, seven hundred seventy-eight".