261975288960 has 1024 divisors, whose sum is σ = 1162020556800. Its totient is φ = 54190080000.

The previous prime is 261975288959. The next prime is 261975289003. The reversal of 261975288960 is 69882579162.

261975288960 is a `hidden beast` number, since 2 + 6 + 19 + 7 + 528 + 8 + 96 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 533554315 + ... + 533554805.

It is an arithmetic number, because the mean of its divisors is an integer number (1134785700).

Almost surely, 2^261975288960 is an apocalyptic number.

261975288960 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 261975288960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (581010278400).

261975288960 is an abundant number, since it is smaller than the sum of its proper divisors (900045267840).

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

261975288960 is a wasteful number, since it uses less digits than its factorization.

261975288960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 938 (or 920 counting only the distinct ones).

The product of its (nonzero) digits is 26127360, while the sum is 63.

The spelling of 261975288960 in words is "two hundred sixty-one billion, nine hundred seventy-five million, two hundred eighty-eight thousand, nine hundred sixty".