681782909 has 16 divisors (see below), whose sum is σ = 772361280. Its totient is φ = 597922560.

The previous prime is 681782903. The next prime is 681782917. The reversal of 681782909 is 909287186.

It is a cyclic number.

It is not a de Polignac number, because 681782909 - 2⁸ = 681782653 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 (681782903) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2402 + ... + 37004.

It is an arithmetic number, because the mean of its divisors is an integer number (48272580).

Almost surely, 2^681782909 is an apocalyptic number.

It is an amenable number.

681782909 is a deficient number, since it is larger than the sum of its proper divisors (90578371).

681782909 is a wasteful number, since it uses less digits than its factorization.

681782909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34700.

The product of its (nonzero) digits is 435456, while the sum is 50.

The square root of 681782909 is about 26110.9729615731. The cubic root of 681782909 is about 880.1338075628.

The spelling of 681782909 in words is "six hundred eighty-one million, seven hundred eighty-two thousand, nine hundred nine".