1555666055 has 4 divisors (see below), whose sum is σ = 1866799272. Its totient is φ = 1244532840.

The previous prime is 1555666051. The next prime is 1555666067. The reversal of 1555666055 is 5506665551.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1555666055 - 2² = 1555666051 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1555665997 and 1555666015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1555666051) 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, 155566601 + ... + 155566610.

It is an arithmetic number, because the mean of its divisors is an integer number (466699818).

Almost surely, 2^1555666055 is an apocalyptic number.

1555666055 is a deficient number, since it is larger than the sum of its proper divisors (311133217).

1555666055 is an equidigital number, since it uses as much as digits as its factorization.

1555666055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 311133216.

The product of its (nonzero) digits is 675000, while the sum is 44.

The square root of 1555666055 is about 39441.9326985887. The cubic root of 1555666055 is about 1158.7029832897.

The spelling of 1555666055 in words is "one billion, five hundred fifty-five million, six hundred sixty-six thousand, fifty-five".