780400816 has 40 divisors (see below), whose sum is σ = 1655057264. Its totient is φ = 354274560.

The previous prime is 780400807. The next prime is 780400823. The reversal of 780400816 is 618004087.

It is a happy number.

780400816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×780400816² = 1218050867226931712, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18066 + ... + 43441.

Almost surely, 2^780400816 is an apocalyptic number.

It is an amenable number.

780400816 is an abundant number, since it is smaller than the sum of its proper divisors (874656448).

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

780400816 is a wasteful number, since it uses less digits than its factorization.

780400816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61589 (or 61583 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 34.

The square root of 780400816 is about 27935.6549234128. The cubic root of 780400816 is about 920.6740554842.

The spelling of 780400816 in words is "seven hundred eighty million, four hundred thousand, eight hundred sixteen".