101561280768 has 108 divisors (see below), whose sum is σ = 293184952060. Its totient is φ = 33812287488.

The previous prime is 101561280763. The next prime is 101561280791. The reversal of 101561280768 is 867082165101.

101561280768 is a `hidden beast` number, since 1 + 0 + 1 + 561 + 2 + 80 + 7 + 6 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 59434539264 + 42126741504 = 243792^2 + 205248^2 .

It is not an unprimeable number, because it can be changed into a prime (101561280763) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1883430 + ... + 1936602.

Almost surely, 2^101561280768 is an apocalyptic number.

101561280768 is a gapful number since it is divisible by the number (18) 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 101561280768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146592476030).

101561280768 is an abundant number, since it is smaller than the sum of its proper divisors (191623671292).

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

101561280768 is an equidigital number, since it uses as much as digits as its factorization.

101561280768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54024 (or 54007 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 101561280768 in words is "one hundred one billion, five hundred sixty-one million, two hundred eighty thousand, seven hundred sixty-eight".