1781320343 has 8 divisors (see below), whose sum is σ = 1945969920. Its totient is φ = 1617122680.

The previous prime is 1781320337. The next prime is 1781320379. The reversal of 1781320343 is 3430231871.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1781320343 - 2¹² = 1781316247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1781320313) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 104705 + ... + 120522.

It is an arithmetic number, because the mean of its divisors is an integer number (243246240).

Almost surely, 2^1781320343 is an apocalyptic number.

1781320343 is a deficient number, since it is larger than the sum of its proper divisors (164649577).

1781320343 is a wasteful number, since it uses less digits than its factorization.

1781320343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225957.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 1781320343 is about 42205.6908840502. The cubic root of 1781320343 is about 1212.2178531936.

The spelling of 1781320343 in words is "one billion, seven hundred eighty-one million, three hundred twenty thousand, three hundred forty-three".