2561331642 has 16 divisors (see below), whose sum is σ = 5124215520. Its totient is φ = 853518512.

The previous prime is 2561331629. The next prime is 2561331667. The reversal of 2561331642 is 2461331652.

2561331642 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 42648 + ... + 83315.

It is an arithmetic number, because the mean of its divisors is an integer number (320263470).

Almost surely, 2^2561331642 is an apocalyptic number.

2561331642 is an abundant number, since it is smaller than the sum of its proper divisors (2562883878).

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

2561331642 is a wasteful number, since it uses less digits than its factorization.

2561331642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129357.

The product of its digits is 25920, while the sum is 33.

The square root of 2561331642 is about 50609.6002948057. The cubic root of 2561331642 is about 1368.2179116205.

The spelling of 2561331642 in words is "two billion, five hundred sixty-one million, three hundred thirty-one thousand, six hundred forty-two".