2561771653 has 16 divisors (see below), whose sum is σ = 3084480000. Its totient is φ = 2078447472.

The previous prime is 2561771651. The next prime is 2561771657. The reversal of 2561771653 is 3561771652.

It is a cyclic number.

It is not a de Polignac number, because 2561771653 - 2¹ = 2561771651 is a prime.

It is a super-2 number, since 2×2561771653² = 13125348004228704818, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2561771651) 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, 159798 + ... + 175096.

It is an arithmetic number, because the mean of its divisors is an integer number (192780000).

Almost surely, 2^2561771653 is an apocalyptic number.

It is an amenable number.

2561771653 is a deficient number, since it is larger than the sum of its proper divisors (522708347).

2561771653 is a wasteful number, since it uses less digits than its factorization.

2561771653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16584.

The product of its digits is 264600, while the sum is 43.

The square root of 2561771653 is about 50613.9472181335. The cubic root of 2561771653 is about 1368.2962558238.

Subtracting 2561771653 from its reverse (3561771652), we obtain a palindrome (999999999).

The spelling of 2561771653 in words is "two billion, five hundred sixty-one million, seven hundred seventy-one thousand, six hundred fifty-three".