1681210440 has 768 divisors, whose sum is σ = 7369689600. Its totient is φ = 322486272.

The previous prime is 1681210387. The next prime is 1681210463. The reversal of 1681210440 is 440121861.

It is a happy number.

1681210440 is a `hidden beast` number, since 1 + 6 + 8 + 1 + 210 + 440 = 666.

It is a zygodrome in base 3.

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 191 ways as a sum of consecutive naturals, for example, 23030244 + ... + 23030316.

It is an arithmetic number, because the mean of its divisors is an integer number (9595950).

Almost surely, 2^1681210440 is an apocalyptic number.

1681210440 is a gapful number since it is divisible by the number (10) 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 1681210440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3684844800).

1681210440 is an abundant number, since it is smaller than the sum of its proper divisors (5688479160).

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

1681210440 is a wasteful number, since it uses less digits than its factorization.

1681210440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 1681210440 is about 41002.5662611500. The cubic root of 1681210440 is about 1189.0698283954.

The spelling of 1681210440 in words is "one billion, six hundred eighty-one million, two hundred ten thousand, four hundred forty".