78566840 has 32 divisors (see below), whose sum is σ = 192846960. Its totient is φ = 28569600.

The previous prime is 78566837. The next prime is 78566849. The reversal of 78566840 is 4866587.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 78566791 and 78566800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78566849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 88841 + ... + 89720.

Almost surely, 2^78566840 is an apocalyptic number.

It is an amenable number.

78566840 is an abundant number, since it is smaller than the sum of its proper divisors (114280120).

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

78566840 is a wasteful number, since it uses less digits than its factorization.

78566840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178583 (or 178579 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 44.

The square root of 78566840 is about 8863.7937701641. The cubic root of 78566840 is about 428.2983769697.

The spelling of 78566840 in words is "seventy-eight million, five hundred sixty-six thousand, eight hundred forty".