1681771008 has 80 divisors (see below), whose sum is σ = 4513148640. Its totient is φ = 556486656.

The previous prime is 1681770947. The next prime is 1681771031. The reversal of 1681771008 is 8001771861.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 209566 + ... + 217442.

It is an arithmetic number, because the mean of its divisors is an integer number (56414358).

Almost surely, 2^1681771008 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1681771008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2256574320).

1681771008 is an abundant number, since it is smaller than the sum of its proper divisors (2831377632).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1681771008 is an equidigital number, since it uses as much as digits as its factorization.

1681771008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8037 (or 8021 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 39.

The square root of 1681771008 is about 41009.4014586899. The cubic root of 1681771008 is about 1189.2019713661.

The spelling of 1681771008 in words is "one billion, six hundred eighty-one million, seven hundred seventy-one thousand, eight".