1780664989 has 8 divisors (see below), whose sum is σ = 1844933760. Its totient is φ = 1716587376.

The previous prime is 1780664981. The next prime is 1780664999. The reversal of 1780664989 is 9894660871.

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 1780664989 - 2³ = 1780664981 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 (1780664981) 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, 28689 + ... + 66214.

It is an arithmetic number, because the mean of its divisors is an integer number (230616720).

Almost surely, 2^1780664989 is an apocalyptic number.

It is an amenable number.

1780664989 is a deficient number, since it is larger than the sum of its proper divisors (64268771).

1780664989 is an equidigital number, since it uses as much as digits as its factorization.

1780664989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95579.

The product of its (nonzero) digits is 5225472, while the sum is 58.

The square root of 1780664989 is about 42197.9263590049. The cubic root of 1780664989 is about 1212.0691752262.

The spelling of 1780664989 in words is "one billion, seven hundred eighty million, six hundred sixty-four thousand, nine hundred eighty-nine".