261573785813 has 8 divisors (see below), whose sum is σ = 261885166848. Its totient is φ = 261262480864.

The previous prime is 261573785747. The next prime is 261573786017. The reversal of 261573785813 is 318587375162.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261573785813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261573785113) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9753020 + ... + 9779802.

It is an arithmetic number, because the mean of its divisors is an integer number (32735645856).

Almost surely, 2^261573785813 is an apocalyptic number.

It is an amenable number.

261573785813 is a deficient number, since it is larger than the sum of its proper divisors (311381035).

261573785813 is a wasteful number, since it uses less digits than its factorization.

261573785813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38043.

The product of its digits is 8467200, while the sum is 56.

The spelling of 261573785813 in words is "two hundred sixty-one billion, five hundred seventy-three million, seven hundred eighty-five thousand, eight hundred thirteen".