1223220155520 has 256 divisors, whose sum is σ = 4294773550080. Its totient is φ = 293658685440.

The previous prime is 1223220155519. The next prime is 1223220155533. The reversal of 1223220155520 is 255510223221.

It is a Harshad number since it is a multiple of its sum of digits (30).

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 31 ways as a sum of consecutive naturals, for example, 1894207 + ... + 2456513.

It is an arithmetic number, because the mean of its divisors is an integer number (16776459180).

Almost surely, 2^{1223220155520} is an apocalyptic number.

1223220155520 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 1223220155520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2147386775040).

1223220155520 is an abundant number, since it is smaller than the sum of its proper divisors (3071553394560).

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

1223220155520 is a wasteful number, since it uses less digits than its factorization.

1223220155520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562443 (or 562431 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

Adding to 1223220155520 its reverse (255510223221), we get a palindrome (1478730378741).

The spelling of 1223220155520 in words is "one trillion, two hundred twenty-three billion, two hundred twenty million, one hundred fifty-five thousand, five hundred twenty".