55578917 has 2 divisors, whose sum is σ = 55578918. Its totient is φ = 55578916.

The previous prime is 55578893. The next prime is 55578923. The reversal of 55578917 is 71987555.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45171841 + 10407076 = 6721^2 + 3226^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55578917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55578947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27789458 + 27789459.

It is an arithmetic number, because the mean of its divisors is an integer number (27789459).

Almost surely, 2^55578917 is an apocalyptic number.

It is an amenable number.

55578917 is a deficient number, since it is larger than the sum of its proper divisors (1).

55578917 is an equidigital number, since it uses as much as digits as its factorization.

55578917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 441000, while the sum is 47.

The square root of 55578917 is about 7455.1268936216. The cubic root of 55578917 is about 381.6248910457.

The spelling of 55578917 in words is "fifty-five million, five hundred seventy-eight thousand, nine hundred seventeen".