55403321 has 2 divisors, whose sum is σ = 55403322. Its totient is φ = 55403320.

The previous prime is 55403287. The next prime is 55403329. The reversal of 55403321 is 12330455.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55056400 + 346921 = 7420^2 + 589^2 .

It is a cyclic number.

It is not a de Polignac number, because 55403321 - 2¹⁴ = 55386937 is a prime.

It is not a weakly prime, because it can be changed into another prime (55403329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27701660 + 27701661.

It is an arithmetic number, because the mean of its divisors is an integer number (27701661).

Almost surely, 2^55403321 is an apocalyptic number.

It is an amenable number.

55403321 is a deficient number, since it is larger than the sum of its proper divisors (1).

55403321 is an equidigital number, since it uses as much as digits as its factorization.

55403321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 55403321 is about 7443.3407150284. The cubic root of 55403321 is about 381.2225652210. Note that the first 3 decimals are identical.

Adding to 55403321 its reverse (12330455), we get a palindrome (67733776).

The spelling of 55403321 in words is "fifty-five million, four hundred three thousand, three hundred twenty-one".