55909989 has 24 divisors (see below), whose sum is σ = 85307040. Its totient is φ = 35188128.

The previous prime is 55909969. The next prime is 55910017. The reversal of 55909989 is 98990955.

55909989 is a `hidden beast` number, since 559 + 0 + 9 + 9 + 89 = 666.

It is not a de Polignac number, because 55909989 - 2¹¹ = 55907941 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55909939) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 94954 + ... + 95540.

It is an arithmetic number, because the mean of its divisors is an integer number (3554460).

Almost surely, 2^55909989 is an apocalyptic number.

It is an amenable number.

55909989 is a deficient number, since it is larger than the sum of its proper divisors (29397051).

55909989 is a wasteful number, since it uses less digits than its factorization.

55909989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1169 (or 1166 counting only the distinct ones).

The product of its (nonzero) digits is 1312200, while the sum is 54.

The square root of 55909989 is about 7477.2982420123. The cubic root of 55909989 is about 382.3811446684.

The spelling of 55909989 in words is "fifty-five million, nine hundred nine thousand, nine hundred eighty-nine".