55661329 has 4 divisors (see below), whose sum is σ = 55698160. Its totient is φ = 55624500.

The previous prime is 55661273. The next prime is 55661339. The reversal of 55661329 is 92316655.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 92316655 = 5 ⋅18463331.

It is a cyclic number.

It is not a de Polignac number, because 55661329 - 2¹⁹ = 55137041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55661339) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16047 + ... + 19204.

It is an arithmetic number, because the mean of its divisors is an integer number (13924540).

Almost surely, 2^55661329 is an apocalyptic number.

It is an amenable number.

55661329 is a deficient number, since it is larger than the sum of its proper divisors (36831).

55661329 is a wasteful number, since it uses less digits than its factorization.

55661329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36830.

The product of its digits is 48600, while the sum is 37.

The square root of 55661329 is about 7460.6520492515. The cubic root of 55661329 is about 381.8134213984.

The spelling of 55661329 in words is "fifty-five million, six hundred sixty-one thousand, three hundred twenty-nine".