1681431709 has 8 divisors (see below), whose sum is σ = 1732918880. Its totient is φ = 1630507536.

The previous prime is 1681431701. The next prime is 1681431743. The reversal of 1681431709 is 9071341861.

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 1681431709 - 2³ = 1681431701 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 (1681431701) 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, 134682 + ... + 146635.

It is an arithmetic number, because the mean of its divisors is an integer number (216614860).

Almost surely, 2^1681431709 is an apocalyptic number.

It is an amenable number.

1681431709 is a deficient number, since it is larger than the sum of its proper divisors (51487171).

1681431709 is a wasteful number, since it uses less digits than its factorization.

1681431709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281499.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 1681431709 is about 41005.2644059272. The cubic root of 1681431709 is about 1189.1219917542.

The spelling of 1681431709 in words is "one billion, six hundred eighty-one million, four hundred thirty-one thousand, seven hundred nine".