1581838366656 has 224 divisors, whose sum is σ = 4358491095040. Its totient is φ = 505873465344.

The previous prime is 1581838366643. The next prime is 1581838366763. The reversal of 1581838366656 is 6566638381851.

It is a hoax number, since the sum of its digits (66) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 610040496 + ... + 610043088.

Almost surely, 2^{1581838366656} is an apocalyptic number.

1581838366656 is a gapful number since it is divisible by the number (16) 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 1581838366656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2179245547520).

1581838366656 is an abundant number, since it is smaller than the sum of its proper divisors (2776652728384).

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

1581838366656 is a wasteful number, since it uses less digits than its factorization.

1581838366656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3811 (or 3801 counting only the distinct ones).

The product of its digits is 149299200, while the sum is 66.

The spelling of 1581838366656 in words is "one trillion, five hundred eighty-one billion, eight hundred thirty-eight million, three hundred sixty-six thousand, six hundred fifty-six".