561256278220872 has 512 divisors, whose sum is σ = 1785546044352000. Its totient is φ = 161920879718400.

The previous prime is 561256278220787. The next prime is 561256278220909. The reversal of 561256278220872 is 278022872652165.

561256278220872 is a `hidden beast` number, since 5 + 6 + 12 + 56 + 278 + 220 + 87 + 2 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 14511351198 + ... + 14511389874.

It is an arithmetic number, because the mean of its divisors is an integer number (3487394617875).

Almost surely, 2^{561256278220872} is an apocalyptic number.

561256278220872 is a gapful number since it is divisible by the number (52) 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 561256278220872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (892773022176000).

561256278220872 is an abundant number, since it is smaller than the sum of its proper divisors (1224289766131128).

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

561256278220872 is a wasteful number, since it uses less digits than its factorization.

561256278220872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41518 (or 41508 counting only the distinct ones).

The product of its (nonzero) digits is 90316800, while the sum is 63.

The spelling of 561256278220872 in words is "five hundred sixty-one trillion, two hundred fifty-six billion, two hundred seventy-eight million, two hundred twenty thousand, eight hundred seventy-two".