1661825362680 has 288 divisors, whose sum is σ = 6416395352640. Its totient is φ = 371763786240.

The previous prime is 1661825362669. The next prime is 1661825362723. The reversal of 1661825362680 is 862635281661.

1661825362680 is a `hidden beast` number, since 1 + 6 + 6 + 1 + 8 + 2 + 5 + 3 + 626 + 8 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 173131 + ... + 1831290.

It is an arithmetic number, because the mean of its divisors is an integer number (22279150530).

Almost surely, 2^{1661825362680} is an apocalyptic number.

1661825362680 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 1661825362680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3208197676320).

1661825362680 is an abundant number, since it is smaller than the sum of its proper divisors (4754569989960).

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

1661825362680 is a wasteful number, since it uses less digits than its factorization.

1661825362680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2004499 (or 2004485 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

The spelling of 1661825362680 in words is "one trillion, six hundred sixty-one billion, eight hundred twenty-five million, three hundred sixty-two thousand, six hundred eighty".