781061511608 has 64 divisors (see below), whose sum is σ = 1719437941440. Its totient is φ = 325598966784.

The previous prime is 781061511577. The next prime is 781061511613. The reversal of 781061511608 is 806115160187.

It is a super-2 number, since 2×781061511608² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7317116 + ... + 7423092.

It is an arithmetic number, because the mean of its divisors is an integer number (26866217835).

Almost surely, 2^781061511608 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 781061511608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (859718970720).

781061511608 is an abundant number, since it is smaller than the sum of its proper divisors (938376429832).

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

781061511608 is a wasteful number, since it uses less digits than its factorization.

781061511608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109584 (or 109580 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 44.

The spelling of 781061511608 in words is "seven hundred eighty-one billion, sixty-one million, five hundred eleven thousand, six hundred eight".