55215533 has 2 divisors, whose sum is σ = 55215534. Its totient is φ = 55215532.

The previous prime is 55215509. The next prime is 55215551. The reversal of 55215533 is 33551255.

55215533 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54140164 + 1075369 = 7358^2 + 1037^2 .

It is a cyclic number.

It is not a de Polignac number, because 55215533 - 2²⁴ = 38438317 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 55215496 and 55215505.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55275533) 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, 27607766 + 27607767.

It is an arithmetic number, because the mean of its divisors is an integer number (27607767).

Almost surely, 2^55215533 is an apocalyptic number.

It is an amenable number.

55215533 is a deficient number, since it is larger than the sum of its proper divisors (1).

55215533 is an equidigital number, since it uses as much as digits as its factorization.

55215533 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11250, while the sum is 29.

The square root of 55215533 is about 7430.7155106356. The cubic root of 55215533 is about 380.7913632797.

Adding to 55215533 its reverse (33551255), we get a palindrome (88766788).

The spelling of 55215533 in words is "fifty-five million, two hundred fifteen thousand, five hundred thirty-three".