1581646228740 has 288 divisors, whose sum is σ = 4970869263360. Its totient is φ = 406846291968.

The previous prime is 1581646228649. The next prime is 1581646228807. The reversal of 1581646228740 is 478226461851.

1581646228740 is a `hidden beast` number, since 1 + 5 + 8 + 1 + 6 + 4 + 622 + 8 + 7 + 4 + 0 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 177968577 + ... + 177977463.

It is an arithmetic number, because the mean of its divisors is an integer number (17259962720).

Almost surely, 2^{1581646228740} is an apocalyptic number.

1581646228740 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 1581646228740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2485434631680).

1581646228740 is an abundant number, since it is smaller than the sum of its proper divisors (3389223034620).

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

1581646228740 is a wasteful number, since it uses less digits than its factorization.

1581646228740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9251 (or 9246 counting only the distinct ones).

The product of its (nonzero) digits is 5160960, while the sum is 54.

The spelling of 1581646228740 in words is "one trillion, five hundred eighty-one billion, six hundred forty-six million, two hundred twenty-eight thousand, seven hundred forty".