55321399 has 4 divisors (see below), whose sum is σ = 63224464. Its totient is φ = 47418336.

The previous prime is 55321367. The next prime is 55321429. The reversal of 55321399 is 99312355.

55321399 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99312355 = 5 ⋅19862471.

It is not a de Polignac number, because 55321399 - 2⁵ = 55321367 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55321319) 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 in 3 ways as a sum of consecutive naturals, for example, 3951522 + ... + 3951535.

It is an arithmetic number, because the mean of its divisors is an integer number (15806116).

Almost surely, 2^55321399 is an apocalyptic number.

55321399 is a deficient number, since it is larger than the sum of its proper divisors (7903065).

55321399 is an equidigital number, since it uses as much as digits as its factorization.

55321399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7903064.

The product of its digits is 36450, while the sum is 37.

The square root of 55321399 is about 7437.8356394855. The cubic root of 55321399 is about 381.0345745612.

It can be divided in two parts, 553 and 21399, that added together give a cube (21952 = 28³).

The spelling of 55321399 in words is "fifty-five million, three hundred twenty-one thousand, three hundred ninety-nine".