55005521 has 2 divisors, whose sum is σ = 55005522.
Its totient is φ = 55005520.
The previous prime is 55005481. The next prime is 55005553. The reversal of 55005521 is 12550055.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 29855296 + 25150225 = 5464^2 + 5015^2
It is a cyclic number.
It is not a de Polignac number, because 55005521 - 222 = 50811217 is a prime.
It is equal to p3282503 and since 55005521 and 3282503 have the same sum of digits, it is a Honaker prime.
It is not a weakly prime, because it can be changed into another prime (55005221) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27502760 + 27502761.
It is an arithmetic number, because the mean of its divisors is an integer number (27502761).
Almost surely, 255005521 is an apocalyptic number.
It is an amenable number.
55005521 is a deficient number, since it is larger than the sum of its proper divisors (1).
55005521 is an equidigital number, since it uses as much as digits as its factorization.
55005521 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 1250, while the sum is 23.
The square root of 55005521 is about 7416.5707034990.
The cubic root of 55005521 is about 380.3079705598.
Adding to 55005521 its reverse (12550055), we get a palindrome (67555576).
The spelling of 55005521 in words is "fifty-five million, five thousand, five hundred twenty-one".