261064471578624 has 1536 divisors, whose sum is σ = 984571807564800. Its totient is φ = 66636333711360.

The previous prime is 261064471578623. The next prime is 261064471578629. The reversal of 261064471578624 is 426875174460162.

261064471578624 is a `hidden beast` number, since 2 + 6 + 1 + 0 + 64 + 471 + 5 + 7 + 86 + 24 = 666.

261064471578624 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (1536).

It is a super-2 number, since 2×261064471578624² (a number of 30 digits) contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (261064471578623) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 9982186732 + ... + 9982212884.

It is an arithmetic number, because the mean of its divisors is an integer number (640997270550).

Almost surely, 2^{261064471578624} is an apocalyptic number.

261064471578624 is a gapful number since it is divisible by the number (24) 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 261064471578624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (492285903782400).

261064471578624 is an abundant number, since it is smaller than the sum of its proper divisors (723507335986176).

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

261064471578624 is a wasteful number, since it uses less digits than its factorization.

261064471578624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26286 (or 26260 counting only the distinct ones).

The product of its (nonzero) digits is 108380160, while the sum is 63.

The spelling of 261064471578624 in words is "two hundred sixty-one trillion, sixty-four billion, four hundred seventy-one million, five hundred seventy-eight thousand, six hundred twenty-four".