55500121 has 8 divisors (see below), whose sum is σ = 61858080. Its totient is φ = 49485888.

The previous prime is 55500089. The next prime is 55500139. The reversal of 55500121 is 12100555.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 55500121 - 2⁵ = 55500089 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55500161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85591 + ... + 86236.

It is an arithmetic number, because the mean of its divisors is an integer number (7732260).

Almost surely, 2^55500121 is an apocalyptic number.

It is an amenable number.

55500121 is a deficient number, since it is larger than the sum of its proper divisors (6357959).

55500121 is a wasteful number, since it uses less digits than its factorization.

55500121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171863.

The product of its (nonzero) digits is 250, while the sum is 19.

The square root of 55500121 is about 7449.8403338595. The cubic root of 55500121 is about 381.4444584981. Note that the first 4 decimals are identical.

Adding to 55500121 its reverse (12100555), we get a palindrome (67600676).

The spelling of 55500121 in words is "fifty-five million, five hundred thousand, one hundred twenty-one".