1681998151680 has 1360 divisors, whose sum is σ = 7527342518784. Its totient is φ = 349081436160.

The previous prime is 1681998151667. The next prime is 1681998151697. The reversal of 1681998151680 is 861518991861.

1681998151680 is a `hidden beast` number, since 16 + 8 + 19 + 98 + 1 + 516 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2043739749 + ... + 2043740571.

Almost surely, 2^{1681998151680} is an apocalyptic number.

1681998151680 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 1681998151680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3763671259392).

1681998151680 is an abundant number, since it is smaller than the sum of its proper divisors (5845344367104).

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

1681998151680 is an frugal number, since it uses more digits than its factorization.

1681998151680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 890 (or 851 counting only the distinct ones).

The product of its (nonzero) digits is 7464960, while the sum is 63.

The spelling of 1681998151680 in words is "one trillion, six hundred eighty-one billion, nine hundred ninety-eight million, one hundred fifty-one thousand, six hundred eighty".