1220125555 has 16 divisors (see below), whose sum is σ = 1652335200. Its totient is φ = 856764160.

The previous prime is 1220125553. The next prime is 1220125637. The reversal of 1220125555 is 5555210221.

It is not a de Polignac number, because 1220125555 - 2¹ = 1220125553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1220125553) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 380890 + ... + 384079.

It is an arithmetic number, because the mean of its divisors is an integer number (103270950).

Almost surely, 2^1220125555 is an apocalyptic number.

1220125555 is a deficient number, since it is larger than the sum of its proper divisors (432209645).

1220125555 is a wasteful number, since it uses less digits than its factorization.

1220125555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 765014.

The product of its (nonzero) digits is 5000, while the sum is 28.

The square root of 1220125555 is about 34930.2956615028. The cubic root of 1220125555 is about 1068.5663844244.

Adding to 1220125555 its reverse (5555210221), we get a palindrome (6775335776).

It can be divided in two parts, 12201255 and 55, that multiplied together give a square (671069025 = 25905²).

The spelling of 1220125555 in words is "one billion, two hundred twenty million, one hundred twenty-five thousand, five hundred fifty-five".