55815 has 12 divisors (see below), whose sum is σ = 90792. Its totient is φ = 29280.

The previous prime is 55813. The next prime is 55817. The reversal of 55815 is 51855.

55815 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (55813) and next prime (55817).

It is not a de Polignac number, because 55815 - 2¹ = 55813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55813) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 885 + ... + 945.

It is an arithmetic number, because the mean of its divisors is an integer number (7566).

2⁵⁵⁸¹⁵ is an apocalyptic number.

55815 is a deficient number, since it is larger than the sum of its proper divisors (34977).

55815 is an equidigital number, since it uses as much as digits as its factorization.

55815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130 (or 69 counting only the distinct ones).

The product of its digits is 1000, while the sum is 24.

The square root of 55815 is about 236.2519841187. The cubic root of 55815 is about 38.2164471449.

The spelling of 55815 in words is "fifty-five thousand, eight hundred fifteen".