261106716805920 has 384 divisors, whose sum is σ = 950554533519360. Its totient is φ = 66868004736000.

The previous prime is 261106716805873. The next prime is 261106716805933. The reversal of 261106716805920 is 29508617601162.

It is a happy number.

261106716805920 is a `hidden beast` number, since 2 + 611 + 0 + 6 + 7 + 16 + 8 + 0 + 5 + 9 + 2 + 0 = 666.

It is a super-2 number, since 2×261106716805920² (a number of 30 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

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 63 ways as a sum of consecutive naturals, for example, 10101835 + ... + 24985205.

It is an arithmetic number, because the mean of its divisors is an integer number (2475402431040).

Almost surely, 2^{261106716805920} is an apocalyptic number.

261106716805920 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 261106716805920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (475277266759680).

261106716805920 is an abundant number, since it is smaller than the sum of its proper divisors (689447816713440).

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

261106716805920 is a wasteful number, since it uses less digits than its factorization.

261106716805920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14883557 (or 14883543 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 54.

The spelling of 261106716805920 in words is "two hundred sixty-one trillion, one hundred six billion, seven hundred sixteen million, eight hundred five thousand, nine hundred twenty".