1681328016 has 225 divisors, whose sum is σ = 5247645249. Its totient is φ = 519602688.

The previous prime is 1681328003. The next prime is 1681328021. The reversal of 1681328016 is 6108231861.

The square root of 1681328016 is 41004.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1308992400 + 372335616 = 36180^2 + 19296^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 25094415 + ... + 25094481.

Almost surely, 2^1681328016 is an apocalyptic number.

1681328016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

1681328016 is the 41004-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1681328016

1681328016 is an abundant number, since it is smaller than the sum of its proper divisors (3566317233).

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

1681328016 is an equidigital number, since it uses as much as digits as its factorization.

1681328016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188 (or 89 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The cubic root of 1681328016 is about 1189.0975470779.

Multiplying 1681328016 by its sum of digits (36), we get a square (60527808576 = 246024²).

1681328016 divided by its sum of digits (36) gives a square (46703556 = 6834²).

Adding to 1681328016 its reverse (6108231861), we get a palindrome (7789559877).

The spelling of 1681328016 in words is "one billion, six hundred eighty-one million, three hundred twenty-eight thousand, sixteen".