1781360640 has 384 divisors, whose sum is σ = 6722352000. Its totient is φ = 445906944.

The previous prime is 1781360629. The next prime is 1781360653. The reversal of 1781360640 is 460631871.

1781360640 is a `hidden beast` number, since 1 + 7 + 8 + 1 + 3 + 6 + 0 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

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 = 1781360595 and 1781360604.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4699971 + ... + 4700349.

It is an arithmetic number, because the mean of its divisors is an integer number (17506125).

Almost surely, 2^1781360640 is an apocalyptic number.

1781360640 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 1781360640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3361176000).

1781360640 is an abundant number, since it is smaller than the sum of its proper divisors (4940991360).

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

1781360640 is a wasteful number, since it uses less digits than its factorization.

1781360640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432 (or 406 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 1781360640 is about 42206.1682695788. The cubic root of 1781360640 is about 1212.2269940489.

The spelling of 1781360640 in words is "one billion, seven hundred eighty-one million, three hundred sixty thousand, six hundred forty".