55805381 has 2 divisors, whose sum is σ = 55805382. Its totient is φ = 55805380.

The previous prime is 55805369. The next prime is 55805401. The reversal of 55805381 is 18350855.

55805381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53728900 + 2076481 = 7330^2 + 1441^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55805381 is a prime.

It is a super-2 number, since 2×55805381² = 6228481097110322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55808381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27902690 + 27902691.

It is an arithmetic number, because the mean of its divisors is an integer number (27902691).

Almost surely, 2^55805381 is an apocalyptic number.

It is an amenable number.

55805381 is a deficient number, since it is larger than the sum of its proper divisors (1).

55805381 is an equidigital number, since it uses as much as digits as its factorization.

55805381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24000, while the sum is 35.

The square root of 55805381 is about 7470.2999270444. The cubic root of 55805381 is about 382.1425164715.

The spelling of 55805381 in words is "fifty-five million, eight hundred five thousand, three hundred eighty-one".