1581399860832 has 240 divisors, whose sum is σ = 5080878910800. Its totient is φ = 478530063360.

The previous prime is 1581399860809. The next prime is 1581399860839. The reversal of 1581399860832 is 2380689931851.

1581399860832 is a `hidden beast` number, since 1 + 5 + 8 + 13 + 9 + 9 + 8 + 608 + 3 + 2 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 1581399860832.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1581399860839) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 20175894 + ... + 20254122.

It is an arithmetic number, because the mean of its divisors is an integer number (21170328795).

Almost surely, 2^{1581399860832} is an apocalyptic number.

1581399860832 is a gapful number since it is divisible by the number (12) 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 1581399860832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2540439455400).

1581399860832 is an abundant number, since it is smaller than the sum of its proper divisors (3499479049968).

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

1581399860832 is a wasteful number, since it uses less digits than its factorization.

1581399860832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78971 (or 78954 counting only the distinct ones).

The product of its (nonzero) digits is 22394880, while the sum is 63.

The spelling of 1581399860832 in words is "one trillion, five hundred eighty-one billion, three hundred ninety-nine million, eight hundred sixty thousand, eight hundred thirty-two".