1681085435904 has 520 divisors, whose sum is σ = 5861795182848. Its totient is φ = 470060236800.

The previous prime is 1681085435899. The next prime is 1681085435917. The reversal of 1681085435904 is 4095345801861.

It is a happy number.

1681085435904 is a `hidden beast` number, since 1 + 6 + 8 + 1 + 0 + 8 + 5 + 43 + 590 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 109146604 + ... + 109162004.

Almost surely, 2^{1681085435904} is an apocalyptic number.

1681085435904 is a gapful number since it is divisible by the number (14) 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 1681085435904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2930897591424).

1681085435904 is an abundant number, since it is smaller than the sum of its proper divisors (4180709746944).

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

1681085435904 is an equidigital number, since it uses as much as digits as its factorization.

1681085435904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15491 (or 15460 counting only the distinct ones).

The product of its (nonzero) digits is 4147200, while the sum is 54.

The spelling of 1681085435904 in words is "one trillion, six hundred eighty-one billion, eighty-five million, four hundred thirty-five thousand, nine hundred four".