2556781355 has 8 divisors (see below), whose sum is σ = 3111351264. Its totient is φ = 2016616000.

The previous prime is 2556781349. The next prime is 2556781373. The reversal of 2556781355 is 5531876552.

It is a happy number.

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

It is not a de Polignac number, because 2556781355 - 2²⁰ = 2555732779 is a prime.

It is a Duffinian number.

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, 3600746 + ... + 3601455.

It is an arithmetic number, because the mean of its divisors is an integer number (388918908).

Almost surely, 2^2556781355 is an apocalyptic number.

2556781355 is a deficient number, since it is larger than the sum of its proper divisors (554569909).

2556781355 is an equidigital number, since it uses as much as digits as its factorization.

2556781355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7202277.

The product of its digits is 1260000, while the sum is 47.

The square root of 2556781355 is about 50564.6255301075. The cubic root of 2556781355 is about 1367.4072038250.

The spelling of 2556781355 in words is "two billion, five hundred fifty-six million, seven hundred eighty-one thousand, three hundred fifty-five".