1563344640 has 648 divisors, whose sum is σ = 6477084432. Its totient is φ = 345047040.

The previous prime is 1563344561. The next prime is 1563344647. The reversal of 1563344640 is 464433651.

1563344640 is a `hidden beast` number, since 1 + 5 + 6 + 3 + 3 + 4 + 4 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1563344595 and 1563344604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1563344647) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 21415644 + ... + 21415716.

Almost surely, 2^1563344640 is an apocalyptic number.

1563344640 is a gapful number since it is divisible by the number (10) 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 1563344640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3238542216).

1563344640 is an abundant number, since it is smaller than the sum of its proper divisors (4913739792).

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

1563344640 is a wasteful number, since it uses less digits than its factorization.

1563344640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 36.

The square root of 1563344640 is about 39539.1532534525. The cubic root of 1563344640 is about 1160.6062625565.

The spelling of 1563344640 in words is "one billion, five hundred sixty-three million, three hundred forty-four thousand, six hundred forty".