55618561 has 2 divisors, whose sum is σ = 55618562. Its totient is φ = 55618560.

The previous prime is 55618513. The next prime is 55618573. The reversal of 55618561 is 16581655.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40564161 + 15054400 = 6369^2 + 3880^2 .

It is a cyclic number.

It is not a de Polignac number, because 55618561 - 2¹³ = 55610369 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 55618561.

It is not a weakly prime, because it can be changed into another prime (55618361) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27809280 + 27809281.

It is an arithmetic number, because the mean of its divisors is an integer number (27809281).

Almost surely, 2^55618561 is an apocalyptic number.

It is an amenable number.

55618561 is a deficient number, since it is larger than the sum of its proper divisors (1).

55618561 is an equidigital number, since it uses as much as digits as its factorization.

55618561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36000, while the sum is 37.

The square root of 55618561 is about 7457.7852610544. The cubic root of 55618561 is about 381.7156061481.

The spelling of 55618561 in words is "fifty-five million, six hundred eighteen thousand, five hundred sixty-one".