2561662809923 has 8 divisors (see below), whose sum is σ = 3081699621120. Its totient is φ = 2080147244040.

The previous prime is 2561662809919. The next prime is 2561662809943. The reversal of 2561662809923 is 3299082661652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2561662809923 - 2² = 2561662809919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2561662809913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9630311183 + ... + 9630311448.

It is an arithmetic number, because the mean of its divisors is an integer number (385212452640).

Almost surely, 2^{2561662809923} is an apocalyptic number.

2561662809923 is a deficient number, since it is larger than the sum of its proper divisors (520036811197).

2561662809923 is a wasteful number, since it uses less digits than its factorization.

2561662809923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19260622657.

The product of its (nonzero) digits is 16796160, while the sum is 59.

The spelling of 2561662809923 in words is "two trillion, five hundred sixty-one billion, six hundred sixty-two million, eight hundred nine thousand, nine hundred twenty-three".