1220243359545 has 48 divisors (see below), whose sum is σ = 2466575529600. Its totient is φ = 557825528736.

The previous prime is 1220243359493. The next prime is 1220243359571. The reversal of 1220243359545 is 5459533420221.

It is a happy number.

1220243359545 is a `hidden beast` number, since 1 + 2 + 2 + 0 + 24 + 33 + 59 + 545 = 666.

It is not a de Polignac number, because 1220243359545 - 2¹¹ = 1220243357497 is a prime.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1220243359545.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 39513019 + ... + 39543888.

It is an arithmetic number, because the mean of its divisors is an integer number (51386990200).

Almost surely, 2^{1220243359545} is an apocalyptic number.

1220243359545 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1220243359545 is an abundant number, since it is smaller than the sum of its proper divisors (1246332170055).

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

1220243359545 is an equidigital number, since it uses as much as digits as its factorization.

1220243359545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79056939 (or 79056922 counting only the distinct ones).

The product of its (nonzero) digits is 1296000, while the sum is 45.

Adding to 1220243359545 its reverse (5459533420221), we get a palindrome (6679776779766).

The spelling of 1220243359545 in words is "one trillion, two hundred twenty billion, two hundred forty-three million, three hundred fifty-nine thousand, five hundred forty-five".