55551909 has 8 divisors (see below), whose sum is σ = 84650560. Its totient is φ = 31743936.

The previous prime is 55551887. The next prime is 55551913. The reversal of 55551909 is 90915555.

It is a happy number.

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

It is not a de Polignac number, because 55551909 - 2¹² = 55547813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55551929) 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, 1322644 + ... + 1322685.

It is an arithmetic number, because the mean of its divisors is an integer number (10581320).

Almost surely, 2^55551909 is an apocalyptic number.

It is an amenable number.

55551909 is a deficient number, since it is larger than the sum of its proper divisors (29098651).

55551909 is a wasteful number, since it uses less digits than its factorization.

55551909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2645339.

The product of its (nonzero) digits is 50625, while the sum is 39.

The square root of 55551909 is about 7453.3153026019. The cubic root of 55551909 is about 381.5630654736.

The spelling of 55551909 in words is "fifty-five million, five hundred fifty-one thousand, nine hundred nine".