781648560 has 480 divisors, whose sum is σ = 3420638208. Its totient is φ = 155105280.

The previous prime is 781648541. The next prime is 781648561. The reversal of 781648560 is 65846187.

It is a happy number.

781648560 is a `hidden beast` number, since 7 + 81 + 6 + 4 + 8 + 560 = 666.

It is a super-2 number, since 2×781648560² = 1221948942700147200, 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 not an unprimeable number, because it can be changed into a prime (781648561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1274814 + ... + 1275426.

Almost surely, 2^781648560 is an apocalyptic number.

781648560 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 781648560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1710319104).

781648560 is an abundant number, since it is smaller than the sum of its proper divisors (2638989648).

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

781648560 is a wasteful number, since it uses less digits than its factorization.

781648560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 673 (or 664 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 45.

The square root of 781648560 is about 27957.9784676933. The cubic root of 781648560 is about 921.1644675108.

The spelling of 781648560 in words is "seven hundred eighty-one million, six hundred forty-eight thousand, five hundred sixty".