261398854080 has 448 divisors, whose sum is σ = 1134965959680. Its totient is φ = 55152119808.

The previous prime is 261398854021. The next prime is 261398854097. The reversal of 261398854080 is 80458893162.

261398854080 is a `hidden beast` number, since 2 + 6 + 1 + 3 + 98 + 8 + 540 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 620007 + ... + 952473.

It is an arithmetic number, because the mean of its divisors is an integer number (2533406160).

Almost surely, 2^261398854080 is an apocalyptic number.

261398854080 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261398854080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (567482979840).

261398854080 is an abundant number, since it is smaller than the sum of its proper divisors (873567105600).

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

261398854080 is a wasteful number, since it uses less digits than its factorization.

261398854080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332513 (or 332497 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 54.

The spelling of 261398854080 in words is "two hundred sixty-one billion, three hundred ninety-eight million, eight hundred fifty-four thousand, eighty".