261575953067520 has 4800 divisors, whose sum is σ = 1223504666689536. Its totient is φ = 52883448791040.

The previous prime is 261575953067417. The next prime is 261575953067557. The reversal of 261575953067520 is 25760359575162.

261575953067520 is a `hidden beast` number, since 2 + 6 + 1 + 5 + 7 + 5 + 9 + 530 + 6 + 75 + 20 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 479 ways as a sum of consecutive naturals, for example, 520031715589 + ... + 520031716091.

Almost surely, 2^{261575953067520} is an apocalyptic number.

261575953067520 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 261575953067520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (611752333344768).

261575953067520 is an abundant number, since it is smaller than the sum of its proper divisors (961928713622016).

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

261575953067520 is a wasteful number, since it uses less digits than its factorization.

261575953067520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 723 (or 691 counting only the distinct ones).

The product of its (nonzero) digits is 119070000, while the sum is 63.

The spelling of 261575953067520 in words is "two hundred sixty-one trillion, five hundred seventy-five billion, nine hundred fifty-three million, sixty-seven thousand, five hundred twenty".