55605640 has 32 divisors (see below), whose sum is σ = 132473880. Its totient is φ = 20933632.

The previous prime is 55605637. The next prime is 55605643. The reversal of 55605640 is 4650655.

It is an interprime number because it is at equal distance from previous prime (55605637) and next prime (55605643).

It can be written as a sum of positive squares in 4 ways, for example, as 54199044 + 1406596 = 7362^2 + 1186^2 .

It is not an unprimeable number, because it can be changed into a prime (55605643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40207 + ... + 41566.

Almost surely, 2^55605640 is an apocalyptic number.

It is an amenable number.

55605640 is an abundant number, since it is smaller than the sum of its proper divisors (76868240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

55605640 is a wasteful number, since it uses less digits than its factorization.

55605640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81801 (or 81797 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 31.

The square root of 55605640 is about 7456.9189347880. The cubic root of 55605640 is about 381.6860444979.

The spelling of 55605640 in words is "fifty-five million, six hundred five thousand, six hundred forty".