55809988 has 24 divisors (see below), whose sum is σ = 106968960. Its totient is φ = 25320480.

The previous prime is 55809967. The next prime is 55809989. The reversal of 55809988 is 88990855.

It is a happy number.

It is a super-2 number, since 2×55809988² = 6229509521120288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (52).

It is not an unprimeable number, because it can be changed into a prime (55809989) 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, 6028 + ... + 12163.

It is an arithmetic number, because the mean of its divisors is an integer number (4457040).

Almost surely, 2^55809988 is an apocalyptic number.

It is an amenable number.

55809988 is a deficient number, since it is larger than the sum of its proper divisors (51158972).

55809988 is a wasteful number, since it uses less digits than its factorization.

55809988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18267 (or 18265 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 52.

The square root of 55809988 is about 7470.6082751005. The cubic root of 55809988 is about 382.1530320771.

The spelling of 55809988 in words is "fifty-five million, eight hundred nine thousand, nine hundred eighty-eight".