1220613555 has 32 divisors (see below), whose sum is σ = 2233672704. Its totient is φ = 557571456.

The previous prime is 1220613553. The next prime is 1220613587. The reversal of 1220613555 is 5553160221.

It is a happy number.

1220613555 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1220613555 - 2¹ = 1220613553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1220613553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 165762 + ... + 172968.

It is an arithmetic number, because the mean of its divisors is an integer number (69802272).

Almost surely, 2^1220613555 is an apocalyptic number.

1220613555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1220613555 is a deficient number, since it is larger than the sum of its proper divisors (1013059149).

1220613555 is a wasteful number, since it uses less digits than its factorization.

1220613555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8835.

The product of its (nonzero) digits is 9000, while the sum is 30.

The square root of 1220613555 is about 34937.2803034237. The cubic root of 1220613555 is about 1068.7088262925.

Adding to 1220613555 its reverse (5553160221), we get a palindrome (6773773776).

The spelling of 1220613555 in words is "one billion, two hundred twenty million, six hundred thirteen thousand, five hundred fifty-five".