1665677555 has 4 divisors (see below), whose sum is σ = 1998813072. Its totient is φ = 1332542040.

The previous prime is 1665677551. The next prime is 1665677567. The reversal of 1665677555 is 5557765661.

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

It is not a de Polignac number, because 1665677555 - 2² = 1665677551 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1665677497 and 1665677506.

It is not an unprimeable number, because it can be changed into a prime (1665677551) 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, 166567751 + ... + 166567760.

It is an arithmetic number, because the mean of its divisors is an integer number (499703268).

Almost surely, 2^1665677555 is an apocalyptic number.

1665677555 is a deficient number, since it is larger than the sum of its proper divisors (333135517).

1665677555 is an equidigital number, since it uses as much as digits as its factorization.

1665677555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333135516.

The product of its digits is 6615000, while the sum is 53.

The square root of 1665677555 is about 40812.7131541141. The cubic root of 1665677555 is about 1185.3965107723.

The spelling of 1665677555 in words is "one billion, six hundred sixty-five million, six hundred seventy-seven thousand, five hundred fifty-five".