1220355211555 has 4 divisors (see below), whose sum is σ = 1464426253872. Its totient is φ = 976284169240.

The previous prime is 1220355211553. The next prime is 1220355211561. The reversal of 1220355211555 is 5551125530221.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1220355211555 - 2¹ = 1220355211553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1220355211553) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 122035521151 + ... + 122035521160.

It is an arithmetic number, because the mean of its divisors is an integer number (366106563468).

Almost surely, 2^{1220355211555} is an apocalyptic number.

1220355211555 is a deficient number, since it is larger than the sum of its proper divisors (244071042317).

1220355211555 is an equidigital number, since it uses as much as digits as its factorization.

1220355211555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244071042316.

The product of its (nonzero) digits is 75000, while the sum is 37.

The spelling of 1220355211555 in words is "one trillion, two hundred twenty billion, three hundred fifty-five million, two hundred eleven thousand, five hundred fifty-five".