2564336778 has 8 divisors (see below), whose sum is σ = 5128673568. Its totient is φ = 854778924.

The previous prime is 2564336741. The next prime is 2564336783. The reversal of 2564336778 is 8776334652.

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

2564336778 is an admirable number.

It is a super-2 number, since 2×2564336778² = 13151646222006842568, which contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 2564336778.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 213694726 + ... + 213694737.

It is an arithmetic number, because the mean of its divisors is an integer number (641084196).

Almost surely, 2^2564336778 is an apocalyptic number.

2564336778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

2564336778 is a wasteful number, since it uses less digits than its factorization.

2564336778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427389468.

The product of its digits is 5080320, while the sum is 51.

The square root of 2564336778 is about 50639.2809783077. The cubic root of 2564336778 is about 1368.7527992603.

The spelling of 2564336778 in words is "two billion, five hundred sixty-four million, three hundred thirty-six thousand, seven hundred seventy-eight".