778407642 has 24 divisors (see below), whose sum is σ = 1687551840. Its totient is φ = 259315080.

The previous prime is 778407601. The next prime is 778407649. The reversal of 778407642 is 246704877.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (778407649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20659 + ... + 44537.

It is an arithmetic number, because the mean of its divisors is an integer number (70314660).

Almost surely, 2^778407642 is an apocalyptic number.

778407642 is an abundant number, since it is smaller than the sum of its proper divisors (909144198).

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

778407642 is a wasteful number, since it uses less digits than its factorization.

778407642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25698 (or 25695 counting only the distinct ones).

The product of its (nonzero) digits is 526848, while the sum is 45.

The square root of 778407642 is about 27899.9577419035. The cubic root of 778407642 is about 919.8895748057.

The spelling of 778407642 in words is "seven hundred seventy-eight million, four hundred seven thousand, six hundred forty-two".