781968804100 has 81 divisors (see below), whose sum is σ = 1865389204021. Its totient is φ = 284316920800.

The previous prime is 781968804047. The next prime is 781968804101. The reversal of 781968804100 is 1408869187.

It is a happy number.

The square root of 781968804100 is 884290.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 281508769476 + 500460034624 = 530574^2 + 707432^2 .

It is a super-2 number, since 2×781968804100² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (781968804101) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 97267881 + ... + 97275919.

Almost surely, 2^781968804100 is an apocalyptic number.

781968804100 is the 884290-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 781968804100

781968804100 is an abundant number, since it is smaller than the sum of its proper divisors (1083420399921).

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

781968804100 is an equidigital number, since it uses as much as digits as its factorization.

781968804100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16114 (or 8057 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 52.

The spelling of 781968804100 in words is "seven hundred eighty-one billion, nine hundred sixty-eight million, eight hundred four thousand, one hundred".