2591994666 has 16 divisors (see below), whose sum is σ = 5206629600. Its totient is φ = 860224848.

The previous prime is 2591994631. The next prime is 2591994761. The reversal of 2591994666 is 6664991952.

It is a happy 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, 941856 + ... + 944603.

It is an arithmetic number, because the mean of its divisors is an integer number (325414350).

Almost surely, 2^2591994666 is an apocalyptic number.

2591994666 is an abundant number, since it is smaller than the sum of its proper divisors (2614634934).

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

2591994666 is a wasteful number, since it uses less digits than its factorization.

2591994666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1886693.

The product of its digits is 6298560, while the sum is 57.

The square root of 2591994666 is about 50911.6358605771. The cubic root of 2591994666 is about 1373.6561487939.

The spelling of 2591994666 in words is "two billion, five hundred ninety-one million, nine hundred ninety-four thousand, six hundred sixty-six".