1281921189120 has 1512 divisors, whose sum is σ = 5445733295520. Its totient is φ = 286475304960.

The previous prime is 1281921189097. The next prime is 1281921189181. The reversal of 1281921189120 is 219811291821.

It is a super-2 number, since 2×1281921189120² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 167 ways as a sum of consecutive naturals, for example, 1734669711 + ... + 1734670449.

It is an arithmetic number, because the mean of its divisors is an integer number (3601675460).

Almost surely, 2^{1281921189120} is an apocalyptic number.

1281921189120 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 1281921189120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2722866647760).

1281921189120 is an abundant number, since it is smaller than the sum of its proper divisors (4163812106400).

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

1281921189120 is an equidigital number, since it uses as much as digits as its factorization.

1281921189120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 815 (or 773 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 45.

The spelling of 1281921189120 in words is "one trillion, two hundred eighty-one billion, nine hundred twenty-one million, one hundred eighty-nine thousand, one hundred twenty".