6782778 has 40 divisors (see below), whose sum is σ = 15354900. Its totient is φ = 2237760.

The previous prime is 6782771. The next prime is 6782801. The reversal of 6782778 is 8772876.

It can be written as a sum of positive squares in 2 ways, for example, as 6671889 + 110889 = 2583^2 + 333^2 .

It is not an unprimeable number, because it can be changed into a prime (6782771) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 23998 + ... + 24278.

Almost surely, 2^6782778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6782778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7677450).

6782778 is an abundant number, since it is smaller than the sum of its proper divisors (8572122).

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

6782778 is a wasteful number, since it uses less digits than its factorization.

6782778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444 (or 435 counting only the distinct ones).

The product of its digits is 263424, while the sum is 45.

The square root of 6782778 is about 2604.3767008634. The cubic root of 6782778 is about 189.2935724823.

The spelling of 6782778 in words is "six million, seven hundred eighty-two thousand, seven hundred seventy-eight".