55520221857 has 4 divisors (see below), whose sum is σ = 74026962480. Its totient is φ = 37013481236.

The previous prime is 55520221849. The next prime is 55520221877. The reversal of 55520221857 is 75812202555.

It is a happy number.

55520221857 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 55520221857 - 2³ = 55520221849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (55520221877) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9253370307 + ... + 9253370312.

It is an arithmetic number, because the mean of its divisors is an integer number (18506740620).

Almost surely, 2^55520221857 is an apocalyptic number.

It is an amenable number.

55520221857 is a deficient number, since it is larger than the sum of its proper divisors (18506740623).

55520221857 is a wasteful number, since it uses less digits than its factorization.

55520221857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18506740622.

The product of its (nonzero) digits is 280000, while the sum is 42.

The spelling of 55520221857 in words is "fifty-five billion, five hundred twenty million, two hundred twenty-one thousand, eight hundred fifty-seven".