2585400866 has 16 divisors (see below), whose sum is σ = 4048644600. Its totient is φ = 1236670848.

The previous prime is 2585400833. The next prime is 2585400869. The reversal of 2585400866 is 6680045852.

It can be written as a sum of positive squares in 4 ways, for example, as 1991747641 + 593653225 = 44629^2 + 24365^2 .

It is not an unprimeable number, because it can be changed into a prime (2585400869) 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, 198155 + ... + 210798.

Almost surely, 2^2585400866 is an apocalyptic number.

2585400866 is a deficient number, since it is larger than the sum of its proper divisors (1463243734).

2585400866 is a wasteful number, since it uses less digits than its factorization.

2585400866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409093.

The product of its (nonzero) digits is 460800, while the sum is 44.

The square root of 2585400866 is about 50846.8373254424. The cubic root of 2585400866 is about 1372.4903406630.

The spelling of 2585400866 in words is "two billion, five hundred eighty-five million, four hundred thousand, eight hundred sixty-six".