3185981681 has 8 divisors (see below), whose sum is σ = 3285675624. Its totient is φ = 3087002880.

The previous prime is 3185981677. The next prime is 3185981719. The reversal of 3185981681 is 1861895813.

It can be written as a sum of positive squares in 4 ways, for example, as 853574656 + 2332407025 = 29216^2 + 48295^2 .

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 3185981681 - 2² = 3185981677 is a prime.

It is a super-2 number, since 2×3185981681² = 20300958543335171522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3185981881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 169730 + ... + 187563.

It is an arithmetic number, because the mean of its divisors is an integer number (410709453).

Almost surely, 2^3185981681 is an apocalyptic number.

It is an amenable number.

3185981681 is a deficient number, since it is larger than the sum of its proper divisors (99693943).

3185981681 is a wasteful number, since it uses less digits than its factorization.

3185981681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357571.

The product of its digits is 414720, while the sum is 50.

The square root of 3185981681 is about 56444.5008924696. The cubic root of 3185981681 is about 1471.4576192296.

The spelling of 3185981681 in words is "three billion, one hundred eighty-five million, nine hundred eighty-one thousand, six hundred eighty-one".