780641680 has 160 divisors (see below), whose sum is σ = 2251355904. Its totient is φ = 245127168.

The previous prime is 780641669. The next prime is 780641711. The reversal of 780641680 is 86146087.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1142619 + ... + 1143301.

Almost surely, 2^780641680 is an apocalyptic number.

780641680 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 780641680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1125677952).

780641680 is an abundant number, since it is smaller than the sum of its proper divisors (1470714224).

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

780641680 is a wasteful number, since it uses less digits than its factorization.

780641680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 873 (or 867 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 780641680 is about 27939.9656406374. The cubic root of 780641680 is about 920.7687651174.

The spelling of 780641680 in words is "seven hundred eighty million, six hundred forty-one thousand, six hundred eighty".