55331813 has 6 divisors (see below), whose sum is σ = 57842694. Its totient is φ = 52925576.

The previous prime is 55331803. The next prime is 55331851. The reversal of 55331813 is 31813355.

It can be written as a sum of positive squares in only one way, i.e., 43270084 + 12061729 = 6578^2 + 3473^2 .

It is not a de Polignac number, because 55331813 - 2²⁴ = 38554597 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55331803) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 51770 + ... + 52827.

It is an arithmetic number, because the mean of its divisors is an integer number (9640449).

Almost surely, 2^55331813 is an apocalyptic number.

It is an amenable number.

55331813 is a deficient number, since it is larger than the sum of its proper divisors (2510881).

55331813 is a wasteful number, since it uses less digits than its factorization.

55331813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104643 (or 104620 counting only the distinct ones).

The product of its digits is 5400, while the sum is 29.

The square root of 55331813 is about 7438.5356757900. The cubic root of 55331813 is about 381.0584823989.

The spelling of 55331813 in words is "fifty-five million, three hundred thirty-one thousand, eight hundred thirteen".