55891321 has 2 divisors, whose sum is σ = 55891322. Its totient is φ = 55891320.

The previous prime is 55891289. The next prime is 55891327. The reversal of 55891321 is 12319855.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50765625 + 5125696 = 7125^2 + 2264^2 .

It is a cyclic number.

It is not a de Polignac number, because 55891321 - 2⁵ = 55891289 is a prime.

It is not a weakly prime, because it can be changed into another prime (55891327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27945660 + 27945661.

It is an arithmetic number, because the mean of its divisors is an integer number (27945661).

Almost surely, 2^55891321 is an apocalyptic number.

It is an amenable number.

55891321 is a deficient number, since it is larger than the sum of its proper divisors (1).

55891321 is an equidigital number, since it uses as much as digits as its factorization.

55891321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10800, while the sum is 34.

The square root of 55891321 is about 7476.0498259442. The cubic root of 55891321 is about 382.3385816967.

The spelling of 55891321 in words is "fifty-five million, eight hundred ninety-one thousand, three hundred twenty-one".