55215555509 has 2 divisors, whose sum is σ = 55215555510. Its totient is φ = 55215555508.

The previous prime is 55215555463. The next prime is 55215555533. The reversal of 55215555509 is 90555551255.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53131633009 + 2083922500 = 230503^2 + 45650^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55215555509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55215555539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27607777754 + 27607777755.

It is an arithmetic number, because the mean of its divisors is an integer number (27607777755).

Almost surely, 2^55215555509 is an apocalyptic number.

It is an amenable number.

55215555509 is a deficient number, since it is larger than the sum of its proper divisors (1).

55215555509 is an equidigital number, since it uses as much as digits as its factorization.

55215555509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1406250, while the sum is 47.

The spelling of 55215555509 in words is "fifty-five billion, two hundred fifteen million, five hundred fifty-five thousand, five hundred nine".