55213609 has 8 divisors (see below), whose sum is σ = 60291360.
Its totient is φ = 50145600.
The previous prime is 55213607. The next prime is 55213619. The reversal of 55213609 is 90631255.
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 55213609 - 21 = 55213607 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (55213607) 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, 14694 + ... + 18064.
It is an arithmetic number, because the mean of its divisors is an integer number (7536420).
Almost surely, 255213609 is an apocalyptic number.
It is an amenable number.
55213609 is a deficient number, since it is larger than the sum of its proper divisors (5077751).
55213609 is a wasteful number, since it uses less digits than its factorization.
55213609 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 4871.
The product of its (nonzero) digits is 8100, while the sum is 31.
The square root of 55213609 is about 7430.5860468741.
The cubic root of 55213609 is about 380.7869403027.
It can be divided in two parts, 552 and 13609, that added together give a square (14161 = 1192).
The spelling of 55213609 in words is "fifty-five million, two hundred thirteen thousand, six hundred nine".