561691101312 has 768 divisors, whose sum is σ = 1880722022400. Its totient is φ = 159357542400.

The previous prime is 561691101299. The next prime is 561691101331. The reversal of 561691101312 is 213101196165.

561691101312 is a `hidden beast` number, since 5 + 616 + 9 + 1 + 1 + 0 + 1 + 31 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1564598989 + ... + 1564599347.

It is an arithmetic number, because the mean of its divisors is an integer number (2448856800).

Almost surely, 2^561691101312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 561691101312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (940361011200).

561691101312 is an abundant number, since it is smaller than the sum of its proper divisors (1319030921088).

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

561691101312 is a wasteful number, since it uses less digits than its factorization.

561691101312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545 (or 530 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

Adding to 561691101312 its reverse (213101196165), we get a palindrome (774792297477).

It can be divided in two parts, 56169 and 1101312, that added together give a triangular number (1157481 = T₁₅₂₁).

The spelling of 561691101312 in words is "five hundred sixty-one billion, six hundred ninety-one million, one hundred one thousand, three hundred twelve".