55500391 has 2 divisors, whose sum is σ = 55500392. Its totient is φ = 55500390.

The previous prime is 55500371. The next prime is 55500413. The reversal of 55500391 is 19300555.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 55500391 - 2⁹ = 55499879 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55500331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27750195 + 27750196.

It is an arithmetic number, because the mean of its divisors is an integer number (27750196).

Almost surely, 2^55500391 is an apocalyptic number.

55500391 is a deficient number, since it is larger than the sum of its proper divisors (1).

55500391 is an equidigital number, since it uses as much as digits as its factorization.

55500391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3375, while the sum is 28.

The square root of 55500391 is about 7449.8584550312. The cubic root of 55500391 is about 381.4450770544.

The spelling of 55500391 in words is "fifty-five million, five hundred thousand, three hundred ninety-one".