555513121 has 4 divisors (see below), whose sum is σ = 556020612. Its totient is φ = 555005632.

The previous prime is 555513109. The next prime is 555513139. The reversal of 555513121 is 121315555.

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

It can be written as a sum of positive squares in 2 ways, for example, as 236390625 + 319122496 = 15375^2 + 17864^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-555513121 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 555513121.

It is not an unprimeable number, because it can be changed into a prime (555513191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 252100 + ... + 254293.

It is an arithmetic number, because the mean of its divisors is an integer number (139005153).

Almost surely, 2^555513121 is an apocalyptic number.

It is an amenable number.

555513121 is a deficient number, since it is larger than the sum of its proper divisors (507491).

555513121 is a wasteful number, since it uses less digits than its factorization.

555513121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 507490.

The product of its digits is 3750, while the sum is 28.

The square root of 555513121 is about 23569.3258495019. The cubic root of 555513121 is about 822.0497603879.

Adding to 555513121 its reverse (121315555), we get a palindrome (676828676).

The spelling of 555513121 in words is "five hundred fifty-five million, five hundred thirteen thousand, one hundred twenty-one".