261238107443040 has 1152 divisors, whose sum is σ = 1149907021885440. Its totient is φ = 52491553652736.

The previous prime is 261238107443029. The next prime is 261238107443087. The reversal of 261238107443040 is 40344701832162.

261238107443040 is a `hidden beast` number, since 2 + 6 + 1 + 238 + 107 + 4 + 4 + 304 + 0 = 666.

It is a super-2 number, since 2×261238107443040² (a number of 30 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 689998429 + ... + 690376931.

It is an arithmetic number, because the mean of its divisors is an integer number (998183178720).

Almost surely, 2^{261238107443040} is an apocalyptic number.

261238107443040 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 261238107443040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (574953510942720).

261238107443040 is an abundant number, since it is smaller than the sum of its proper divisors (888668914442400).

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

261238107443040 is a wasteful number, since it uses less digits than its factorization.

261238107443040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378796 (or 378785 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 45.

The spelling of 261238107443040 in words is "two hundred sixty-one trillion, two hundred thirty-eight billion, one hundred seven million, four hundred forty-three thousand, forty".