261551107678336 has 256 divisors, whose sum is σ = 634617346176000. Its totient is φ = 104883409612800.

The previous prime is 261551107678331. The next prime is 261551107678361. The reversal of 261551107678336 is 633876701155162.

It is not an unprimeable number, because it can be changed into a prime (261551107678331) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 470282470 + ... + 470838298.

It is an arithmetic number, because the mean of its divisors is an integer number (2478974008500).

Almost surely, 2^{261551107678336} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261551107678336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (317308673088000).

261551107678336 is an abundant number, since it is smaller than the sum of its proper divisors (373066238497664).

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

261551107678336 is a wasteful number, since it uses less digits than its factorization.

261551107678336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556211 (or 556199 counting only the distinct ones).

The product of its (nonzero) digits is 38102400, while the sum is 61.

The spelling of 261551107678336 in words is "two hundred sixty-one trillion, five hundred fifty-one billion, one hundred seven million, six hundred seventy-eight thousand, three hundred thirty-six".