55171523621 has 2 divisors, whose sum is σ = 55171523622. Its totient is φ = 55171523620.

The previous prime is 55171523591. The next prime is 55171523633. The reversal of 55171523621 is 12632517155.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27652031521 + 27519492100 = 166289^2 + 165890^2 .

It is a cyclic number.

It is not a de Polignac number, because 55171523621 - 2⁶ = 55171523557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55171523651) 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, 27585761810 + 27585761811.

It is an arithmetic number, because the mean of its divisors is an integer number (27585761811).

Almost surely, 2^55171523621 is an apocalyptic number.

It is an amenable number.

55171523621 is a deficient number, since it is larger than the sum of its proper divisors (1).

55171523621 is an equidigital number, since it uses as much as digits as its factorization.

55171523621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63000, while the sum is 38.

The spelling of 55171523621 in words is "fifty-five billion, one hundred seventy-one million, five hundred twenty-three thousand, six hundred twenty-one".