1155217489920 has 1216 divisors, whose sum is σ = 4622449735680. Its totient is φ = 275188285440.

The previous prime is 1155217489891. The next prime is 1155217489939. The reversal of 1155217489920 is 299847125511.

1155217489920 is a `hidden beast` number, since 1 + 1 + 5 + 521 + 7 + 4 + 8 + 99 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 37265080305 + ... + 37265080335.

Almost surely, 2^{1155217489920} is an apocalyptic number.

1155217489920 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 1155217489920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2311224867840).

1155217489920 is an abundant number, since it is smaller than the sum of its proper divisors (3467232245760).

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

1155217489920 is an frugal number, since it uses more digits than its factorization.

1155217489920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106 (or 54 counting only the distinct ones).

The product of its (nonzero) digits is 1814400, while the sum is 54.

The spelling of 1155217489920 in words is "one trillion, one hundred fifty-five billion, two hundred seventeen million, four hundred eighty-nine thousand, nine hundred twenty".