778671 has 12 divisors (see below), whose sum is σ = 1132560. Its totient is φ = 515520.

The previous prime is 778667. The next prime is 778681. The reversal of 778671 is 176877.

It is not a de Polignac number, because 778671 - 2² = 778667 is a prime.

778671 is a lucky number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 778671.

It is not an unprimeable number, because it can be changed into a prime (778681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1990 + ... + 2348.

It is an arithmetic number, because the mean of its divisors is an integer number (94380).

2⁷⁷⁸⁶⁷¹ is an apocalyptic number.

778671 is a deficient number, since it is larger than the sum of its proper divisors (353889).

778671 is a wasteful number, since it uses less digits than its factorization.

778671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 606 (or 603 counting only the distinct ones).

The product of its digits is 16464, while the sum is 36.

The square root of 778671 is about 882.4233677776. The cubic root of 778671 is about 91.9993304929. Note that the first 3 decimals are identical.

The spelling of 778671 in words is "seven hundred seventy-eight thousand, six hundred seventy-one".