55115553 has 4 divisors (see below), whose sum is σ = 73487408. Its totient is φ = 36743700.

The previous prime is 55115549. The next prime is 55115591. The reversal of 55115553 is 35551155.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 55115553 - 2² = 55115549 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 55115553.

It is not an unprimeable number, because it can be changed into a prime (55115503) 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, 9185923 + ... + 9185928.

It is an arithmetic number, because the mean of its divisors is an integer number (18371852).

Almost surely, 2^55115553 is an apocalyptic number.

It is an amenable number.

55115553 is a deficient number, since it is larger than the sum of its proper divisors (18371855).

55115553 is a wasteful number, since it uses less digits than its factorization.

55115553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18371854.

The product of its digits is 9375, while the sum is 30.

The square root of 55115553 is about 7423.9849811270. The cubic root of 55115553 is about 380.5613886055.

The spelling of 55115553 in words is "fifty-five million, one hundred fifteen thousand, five hundred fifty-three".