781648080 has 80 divisors (see below), whose sum is σ = 2429338560. Its totient is φ = 207903744.

The previous prime is 781648079. The next prime is 781648097. The reversal of 781648080 is 80846187.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×781648080² = 1221947441935372800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94179 + ... + 102141.

It is an arithmetic number, because the mean of its divisors is an integer number (30366732).

Almost surely, 2^781648080 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 781648080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1214669280).

781648080 is an abundant number, since it is smaller than the sum of its proper divisors (1647690480).

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

781648080 is a wasteful number, since it uses less digits than its factorization.

781648080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8388 (or 8382 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 42.

The square root of 781648080 is about 27957.9698833803. The cubic root of 781648080 is about 921.1642789525.

The spelling of 781648080 in words is "seven hundred eighty-one million, six hundred forty-eight thousand, eighty".