55115120 has 20 divisors (see below), whose sum is σ = 128142840. Its totient is φ = 22046016.

The previous prime is 55115083. The next prime is 55115129. The reversal of 55115120 is 2151155.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×55115120² = 6075352905228800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 55115092 and 55115101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55115129) 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, 344390 + ... + 344549.

It is an arithmetic number, because the mean of its divisors is an integer number (6407142).

Almost surely, 2^55115120 is an apocalyptic number.

It is an amenable number.

55115120 is an abundant number, since it is smaller than the sum of its proper divisors (73027720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

55115120 is a wasteful number, since it uses less digits than its factorization.

55115120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 688952 (or 688946 counting only the distinct ones).

The product of its (nonzero) digits is 250, while the sum is 20.

The square root of 55115120 is about 7423.9558188341. The cubic root of 55115120 is about 380.5603920114.

Adding to 55115120 its reverse (2151155), we get a palindrome (57266275).

The spelling of 55115120 in words is "fifty-five million, one hundred fifteen thousand, one hundred twenty".