781069680 has 120 divisors (see below), whose sum is σ = 2687171760. Its totient is φ = 203197440.

The previous prime is 781069669. The next prime is 781069699. The reversal of 781069680 is 86960187.

It is a happy number.

781069680 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 (120).

It is a super-2 number, since 2×781069680² = 1220139690030604800, which 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 23 ways as a sum of consecutive naturals, for example, 16291 + ... + 42749.

It is an arithmetic number, because the mean of its divisors is an integer number (22393098).

Almost surely, 2^781069680 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 781069680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1343585880).

781069680 is an abundant number, since it is smaller than the sum of its proper divisors (1906102080).

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

781069680 is a wasteful number, since it uses less digits than its factorization.

781069680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26519 (or 26510 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 781069680 is about 27947.6238703758. The cubic root of 781069680 is about 920.9370100547.

The spelling of 781069680 in words is "seven hundred eighty-one million, sixty-nine thousand, six hundred eighty".