65778856 has 48 divisors (see below), whose sum is σ = 145726560. Its totient is φ = 27593280.

The previous prime is 65778851. The next prime is 65778857. The reversal of 65778856 is 65887756.

It is a Harshad number since it is a multiple of its sum of digits (52).

It is not an unprimeable number, because it can be changed into a prime (65778851) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12661 + ... + 17083.

It is an arithmetic number, because the mean of its divisors is an integer number (3035970).

Almost surely, 2^65778856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65778856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72863280).

65778856 is an abundant number, since it is smaller than the sum of its proper divisors (79947704).

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

65778856 is a wasteful number, since it uses less digits than its factorization.

65778856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4466 (or 4449 counting only the distinct ones).

The product of its digits is 2822400, while the sum is 52.

The square root of 65778856 is about 8110.4165121158. The cubic root of 65778856 is about 403.6721353933.

Subtracting 65778856 from its reverse (65887756), we obtain a square (108900 = 330²).

The spelling of 65778856 in words is "sixty-five million, seven hundred seventy-eight thousand, eight hundred fifty-six".