55420009 has 4 divisors (see below), whose sum is σ = 55560004. Its totient is φ = 55280016.

The previous prime is 55419929. The next prime is 55420039. The reversal of 55420009 is 90002455.

55420009 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 32809984 + 22610025 = 5728^2 + 4755^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55420009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55420039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69402 + ... + 70195.

It is an arithmetic number, because the mean of its divisors is an integer number (13890001).

Almost surely, 2^55420009 is an apocalyptic number.

It is an amenable number.

55420009 is a deficient number, since it is larger than the sum of its proper divisors (139995).

55420009 is a wasteful number, since it uses less digits than its factorization.

55420009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139994.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 55420009 is about 7444.4616326501. The cubic root of 55420009 is about 381.2608373162.

It can be divided in two parts, 554 and 20009, that multiplied together give a triangular number (11084986 = T₄₇₀₈).

The spelling of 55420009 in words is "fifty-five million, four hundred twenty thousand, nine".