861961247616 has 512 divisors, whose sum is σ = 2787433021440. Its totient is φ = 230833152000.

The previous prime is 861961247599. The next prime is 861961247629. The reversal of 861961247616 is 616742169168.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 340560271 + ... + 340562801.

It is an arithmetic number, because the mean of its divisors is an integer number (5444205120).

Almost surely, 2^861961247616 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 861961247616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1393716510720).

861961247616 is an abundant number, since it is smaller than the sum of its proper divisors (1925471773824).

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

861961247616 is a wasteful number, since it uses less digits than its factorization.

861961247616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2714 (or 2702 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 57.

The spelling of 861961247616 in words is "eight hundred sixty-one billion, nine hundred sixty-one million, two hundred forty-seven thousand, six hundred sixteen".