778431 has 8 divisors (see below), whose sum is σ = 1042480. Its totient is φ = 516672.

The previous prime is 778417. The next prime is 778439. The reversal of 778431 is 134877.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 778431 - 2⁹ = 777919 is a prime.

It is a super-2 number, since 2×778431² = 1211909643522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778439) 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 7 ways as a sum of consecutive naturals, for example, 525 + ... + 1353.

It is an arithmetic number, because the mean of its divisors is an integer number (130310).

2⁷⁷⁸⁴³¹ is an apocalyptic number.

778431 is a deficient number, since it is larger than the sum of its proper divisors (264049).

778431 is a wasteful number, since it uses less digits than its factorization.

778431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1145.

The product of its digits is 4704, while the sum is 30.

The square root of 778431 is about 882.2873681517. The cubic root of 778431 is about 91.9898775883.

The spelling of 778431 in words is "seven hundred seventy-eight thousand, four hundred thirty-one".