7781294855880 has 768 divisors, whose sum is σ = 33820312780800. Its totient is φ = 1505182279680.

The previous prime is 7781294855879. The next prime is 7781294855959. The reversal of 7781294855880 is 885584921877.

7781294855880 is a `hidden beast` number, since 7 + 7 + 8 + 1 + 29 + 48 + 558 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 7781294855799 and 7781294855808.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 19094007 + ... + 19497273.

It is an arithmetic number, because the mean of its divisors is an integer number (44036865600).

Almost surely, 2^{7781294855880} is an apocalyptic number.

7781294855880 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 7781294855880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16910156390400).

7781294855880 is an abundant number, since it is smaller than the sum of its proper divisors (26039017924920).

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

7781294855880 is a wasteful number, since it uses less digits than its factorization.

7781294855880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 403354 (or 403347 counting only the distinct ones).

The product of its (nonzero) digits is 361267200, while the sum is 72.

The spelling of 7781294855880 in words is "seven trillion, seven hundred eighty-one billion, two hundred ninety-four million, eight hundred fifty-five thousand, eight hundred eighty".