55171509 has 4 divisors (see below), whose sum is σ = 73562016. Its totient is φ = 36781004.

The previous prime is 55171499. The next prime is 55171531. The reversal of 55171509 is 90517155.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 55171509 - 2⁷ = 55171381 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 55171509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55173509) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9195249 + ... + 9195254.

It is an arithmetic number, because the mean of its divisors is an integer number (18390504).

Almost surely, 2^55171509 is an apocalyptic number.

It is an amenable number.

55171509 is a deficient number, since it is larger than the sum of its proper divisors (18390507).

55171509 is a wasteful number, since it uses less digits than its factorization.

55171509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18390506.

The product of its (nonzero) digits is 7875, while the sum is 33.

The square root of 55171509 is about 7427.7526210826. The cubic root of 55171509 is about 380.6901332126.

The spelling of 55171509 in words is "fifty-five million, one hundred seventy-one thousand, five hundred nine".