2561794642 has 16 divisors (see below), whose sum is σ = 4231209312. Its totient is φ = 1153568320.

The previous prime is 2561794639. The next prime is 2561794657. The reversal of 2561794642 is 2464971652.

It is a junction number, because it is equal to n+sod(n) for n = 2561794592 and 2561794601.

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, 541783 + ... + 546490.

It is an arithmetic number, because the mean of its divisors is an integer number (264450582).

Almost surely, 2^2561794642 is an apocalyptic number.

2561794642 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

2561794642 is a deficient number, since it is larger than the sum of its proper divisors (1669414670).

2561794642 is a wasteful number, since it uses less digits than its factorization.

2561794642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1088393.

The product of its digits is 725760, while the sum is 46.

The square root of 2561794642 is about 50614.1743190581. The cubic root of 2561794642 is about 1368.3003487814.

The spelling of 2561794642 in words is "two billion, five hundred sixty-one million, seven hundred ninety-four thousand, six hundred forty-two".