781305406560 has 480 divisors, whose sum is σ = 3160422619200. Its totient is φ = 178065174528.

The previous prime is 781305406517. The next prime is 781305406577. The reversal of 781305406560 is 65604503187.

781305406560 is a `hidden beast` number, since 7 + 8 + 1 + 30 + 54 + 0 + 6 + 560 = 666.

781305406560 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (480).

It is a super-2 number, since 2×781305406560² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 31648942 + ... + 31673618.

It is an arithmetic number, because the mean of its divisors is an integer number (6584213790).

Almost surely, 2^781305406560 is an apocalyptic number.

781305406560 is a gapful number since it is divisible by the number (70) 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 781305406560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1580211309600).

781305406560 is an abundant number, since it is smaller than the sum of its proper divisors (2379117212640).

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

781305406560 is a wasteful number, since it uses less digits than its factorization.

781305406560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25060 (or 25043 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 45.

The spelling of 781305406560 in words is "seven hundred eighty-one billion, three hundred five million, four hundred six thousand, five hundred sixty".