1681440768 has 300 divisors, whose sum is σ = 5772758992. Its totient is φ = 477757440.

The previous prime is 1681440767. The next prime is 1681440769. The reversal of 1681440768 is 8670441861.

It is an interprime number because it is at equal distance from previous prime (1681440767) and next prime (1681440769).

It is not an unprimeable number, because it can be changed into a prime (1681440767) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 9289638 + ... + 9289818.

Almost surely, 2^1681440768 is an apocalyptic number.

1681440768 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1681440768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2886379496).

1681440768 is an abundant number, since it is smaller than the sum of its proper divisors (4091318224).

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

1681440768 is an frugal number, since it uses more digits than its factorization.

1681440768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228 (or 193 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 45.

The square root of 1681440768 is about 41005.3748672049. The cubic root of 1681440768 is about 1189.1241272828.

The spelling of 1681440768 in words is "one billion, six hundred eighty-one million, four hundred forty thousand, seven hundred sixty-eight".