561640420351068 has 96 divisors (see below), whose sum is σ = 1372751515140096. Its totient is φ = 178383540468672.

The previous prime is 561640420351067. The next prime is 561640420351097. The reversal of 561640420351068 is 860153024046165.

It is a self number, because there is not a number n which added to its sum of digits gives 561640420351068.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561640420351067) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 86301105 + ... + 92580567.

It is an arithmetic number, because the mean of its divisors is an integer number (14299494949376).

Almost surely, 2^{561640420351068} 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 561640420351068, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (686375757570048).

561640420351068 is an abundant number, since it is smaller than the sum of its proper divisors (811111094789028).

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

561640420351068 is a wasteful number, since it uses less digits than its factorization.

561640420351068 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6280743 (or 6280741 counting only the distinct ones).

The product of its (nonzero) digits is 4147200, while the sum is 51.

The spelling of 561640420351068 in words is "five hundred sixty-one trillion, six hundred forty billion, four hundred twenty million, three hundred fifty-one thousand, sixty-eight".