6777840 has 80 divisors (see below), whose sum is σ = 21712896. Its totient is φ = 1747200.

The previous prime is 6777839. The next prime is 6777923. The reversal of 6777840 is 487776.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6985 + ... + 7895.

Almost surely, 2^6777840 is an apocalyptic number.

6777840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6777840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10856448).

6777840 is an abundant number, since it is smaller than the sum of its proper divisors (14935056).

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

6777840 is a wasteful number, since it uses less digits than its factorization.

6777840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 958 (or 952 counting only the distinct ones).

The product of its (nonzero) digits is 65856, while the sum is 39.

The square root of 6777840 is about 2603.4285087169. The cubic root of 6777840 is about 189.2476248097.

Subtracting from 6777840 its reverse (487776), we obtain a square (6290064 = 2508²).

The spelling of 6777840 in words is "six million, seven hundred seventy-seven thousand, eight hundred forty".