2585987778 has 32 divisors (see below), whose sum is σ = 5662132992. Its totient is φ = 780858000.

The previous prime is 2585987777. The next prime is 2585987783. The reversal of 2585987778 is 8777895852.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is not an unprimeable number, because it can be changed into a prime (2585987777) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50548 + ... + 87903.

It is an arithmetic number, because the mean of its divisors is an integer number (176941656).

Almost surely, 2^2585987778 is an apocalyptic number.

2585987778 is an abundant number, since it is smaller than the sum of its proper divisors (3076145214).

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

2585987778 is a wasteful number, since it uses less digits than its factorization.

2585987778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138750.

The product of its digits is 79027200, while the sum is 66.

The square root of 2585987778 is about 50852.6083696795. The cubic root of 2585987778 is about 1372.5941891757.

The spelling of 2585987778 in words is "two billion, five hundred eighty-five million, nine hundred eighty-seven thousand, seven hundred seventy-eight".