1781404560 has 120 divisors (see below), whose sum is σ = 6442780344. Its totient is φ = 438497280.

The previous prime is 1781404477. The next prime is 1781404567. The reversal of 1781404560 is 654041871.

It is a happy number.

1781404560 is a `hidden beast` number, since 17 + 81 + 4 + 0 + 4 + 560 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 386830224 + 1394574336 = 19668^2 + 37344^2 .

It is a tau number, because it is divible by the number of its divisors (120).

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

It is not an unprimeable number, because it can be changed into a prime (1781404567) 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 23 ways as a sum of consecutive naturals, for example, 85801 + ... + 104520.

Almost surely, 2^1781404560 is an apocalyptic number.

1781404560 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1781404560 is an abundant number, since it is smaller than the sum of its proper divisors (4661375784).

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

1781404560 is a wasteful number, since it uses less digits than its factorization.

1781404560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190353 (or 190344 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 1781404560 is about 42206.6885694673. The cubic root of 1781404560 is about 1212.2369565781.

The spelling of 1781404560 in words is "one billion, seven hundred eighty-one million, four hundred four thousand, five hundred sixty".