55555517 has 2 divisors, whose sum is σ = 55555518. Its totient is φ = 55555516.

The previous prime is 55555481. The next prime is 55555523. The reversal of 55555517 is 71555555.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51998521 + 3556996 = 7211^2 + 1886^2 .

It is a cyclic number.

It is not a de Polignac number, because 55555517 - 2¹⁸ = 55293373 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55555547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27777758 + 27777759.

It is an arithmetic number, because the mean of its divisors is an integer number (27777759).

Almost surely, 2^55555517 is an apocalyptic number.

It is an amenable number.

55555517 is a deficient number, since it is larger than the sum of its proper divisors (1).

55555517 is an equidigital number, since it uses as much as digits as its factorization.

55555517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 109375, while the sum is 38.

The square root of 55555517 is about 7453.5573386136. The cubic root of 55555517 is about 381.5713259142.

Adding to 55555517 its sum of digits (38), we get a palindrome (55555555).

The spelling of 55555517 in words is "fifty-five million, five hundred fifty-five thousand, five hundred seventeen".