776640 has 56 divisors (see below), whose sum is σ = 2468880. Its totient is φ = 206848.

The previous prime is 776627. The next prime is 776651. The reversal of 776640 is 46677.

776640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an Ulam number.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 776598 and 776607.

It is a congruent number.

It is an unprimeable number.

776640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 556 + ... + 1364.

2⁷⁷⁶⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 776640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1234440).

776640 is an abundant number, since it is smaller than the sum of its proper divisors (1692240).

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

776640 is a wasteful number, since it uses less digits than its factorization.

776640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 829 (or 819 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 30.

The square root of 776640 is about 881.2718082408. The cubic root of 776640 is about 91.9192738624.

The spelling of 776640 in words is "seven hundred seventy-six thousand, six hundred forty".