15555555553 has 4 divisors (see below), whose sum is σ = 15622317828. Its totient is φ = 15488793280.

The previous prime is 15555555541. The next prime is 15555555581. The reversal of 15555555553 is 35555555551.

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 8036584609 + 7518970944 = 89647^2 + 86712^2 .

It is a cyclic number.

It is not a de Polignac number, because 15555555553 - 2²⁹ = 15018684641 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15555555497 and 15555555506.

It is not an unprimeable number, because it can be changed into a prime (15555555583) 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, 33380788 + ... + 33381253.

It is an arithmetic number, because the mean of its divisors is an integer number (3905579457).

Almost surely, 2^15555555553 is an apocalyptic number.

It is an amenable number.

15555555553 is a deficient number, since it is larger than the sum of its proper divisors (66762275).

15555555553 is an equidigital number, since it uses as much as digits as its factorization.

15555555553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66762274.

The product of its digits is 5859375, while the sum is 49.

The spelling of 15555555553 in words is "fifteen billion, five hundred fifty-five million, five hundred fifty-five thousand, five hundred fifty-three".