261544466222430 has 128 divisors (see below), whose sum is σ = 659721718656000. Its totient is φ = 66232148742144.

The previous prime is 261544466222401. The next prime is 261544466222441. The reversal of 261544466222430 is 34222664445162.

It is a super-3 number, since 3×261544466222430³ (a number of 44 digits) contains 333 as substring.

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, 206737141 + ... + 207998399.

It is an arithmetic number, because the mean of its divisors is an integer number (5154075927000).

Almost surely, 2^{261544466222430} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261544466222430, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (329860859328000).

261544466222430 is an abundant number, since it is smaller than the sum of its proper divisors (398177252433570).

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

261544466222430 is a wasteful number, since it uses less digits than its factorization.

261544466222430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1263458.

The product of its (nonzero) digits is 13271040, while the sum is 51.

The spelling of 261544466222430 in words is "two hundred sixty-one trillion, five hundred forty-four billion, four hundred sixty-six million, two hundred twenty-two thousand, four hundred thirty".