1781384540 has 24 divisors (see below), whose sum is σ = 4028670240. Its totient is φ = 657741888.

The previous prime is 1781384513. The next prime is 1781384587. The reversal of 1781384540 is 454831871.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3425480 + ... + 3425999.

It is an arithmetic number, because the mean of its divisors is an integer number (167861260).

Almost surely, 2^1781384540 is an apocalyptic number.

1781384540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1781384540 is an abundant number, since it is smaller than the sum of its proper divisors (2247285700).

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

1781384540 is a wasteful number, since it uses less digits than its factorization.

1781384540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6851501 (or 6851499 counting only the distinct ones).

The product of its (nonzero) digits is 107520, while the sum is 41.

The square root of 1781384540 is about 42206.4514025996. The cubic root of 1781384540 is about 1212.2324153909.

The spelling of 1781384540 in words is "one billion, seven hundred eighty-one million, three hundred eighty-four thousand, five hundred forty".