1581039987600 has 240 divisors, whose sum is σ = 5165647155200. Its totient is φ = 413275599360.

The previous prime is 1581039987589. The next prime is 1581039987601. The reversal of 1581039987600 is 67899301851.

It is a tau number, because it is divible by the number of its divisors (240).

It is not an unprimeable number, because it can be changed into a prime (1581039987601) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 13117209 + ... + 13237191.

Almost surely, 2^{1581039987600} is an apocalyptic number.

1581039987600 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 1581039987600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2582823577600).

1581039987600 is an abundant number, since it is smaller than the sum of its proper divisors (3584607167600).

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

1581039987600 is a wasteful number, since it uses less digits than its factorization.

1581039987600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120222 (or 120211 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 57.

The spelling of 1581039987600 in words is "one trillion, five hundred eighty-one billion, thirty-nine million, nine hundred eighty-seven thousand, six hundred".