55920009 has 8 divisors (see below), whose sum is σ = 75673120. Its totient is φ = 36723456.

The previous prime is 55919999. The next prime is 55920031. The reversal of 55920009 is 90002955.

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

It is not a de Polignac number, because 55920009 - 2⁴ = 55919993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55920049) 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, 138904 + ... + 139305.

It is an arithmetic number, because the mean of its divisors is an integer number (9459140).

Almost surely, 2^55920009 is an apocalyptic number.

It is an amenable number.

55920009 is a deficient number, since it is larger than the sum of its proper divisors (19753111).

55920009 is a wasteful number, since it uses less digits than its factorization.

55920009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278279.

The product of its (nonzero) digits is 4050, while the sum is 30.

The square root of 55920009 is about 7477.9682401037. The cubic root of 55920009 is about 382.4039863244.

The spelling of 55920009 in words is "fifty-five million, nine hundred twenty thousand, nine".