261285543552 has 512 divisors, whose sum is σ = 840994928640. Its totient is φ = 70900121600.

The previous prime is 261285543517. The next prime is 261285543557. The reversal of 261285543552 is 255345582162.

It is a Harshad number since it is a multiple of its sum of digits (48).

Its product of digits (2880000) is a multiple of the sum of its prime divisors (900).

It is not an unprimeable number, because it can be changed into a prime (261285543557) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 464094823 + ... + 464095385.

It is an arithmetic number, because the mean of its divisors is an integer number (1642568220).

Almost surely, 2^261285543552 is an apocalyptic number.

261285543552 is a gapful number since it is divisible by the number (22) 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 261285543552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (420497464320).

261285543552 is an abundant number, since it is smaller than the sum of its proper divisors (579709385088).

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

261285543552 is a wasteful number, since it uses less digits than its factorization.

261285543552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 912 (or 900 counting only the distinct ones).

The product of its digits is 2880000, while the sum is 48.

The spelling of 261285543552 in words is "two hundred sixty-one billion, two hundred eighty-five million, five hundred forty-three thousand, five hundred fifty-two".