1555645165 has 16 divisors (see below), whose sum is σ = 1915398576. Its totient is φ = 1212198400.

The previous prime is 1555645139. The next prime is 1555645177. The reversal of 1555645165 is 5615465551.

It can be written as a sum of positive squares in 8 ways, for example, as 720492964 + 835152201 = 26842^2 + 28899^2 .

It is not a de Polignac number, because 1555645165 - 2⁷ = 1555645037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 128055 + ... + 139675.

It is an arithmetic number, because the mean of its divisors is an integer number (119712411).

Almost surely, 2^1555645165 is an apocalyptic number.

It is an amenable number.

1555645165 is a deficient number, since it is larger than the sum of its proper divisors (359753411).

1555645165 is a wasteful number, since it uses less digits than its factorization.

1555645165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12320.

The product of its digits is 450000, while the sum is 43.

The square root of 1555645165 is about 39441.6678780196. The cubic root of 1555645165 is about 1158.6977967837.

The spelling of 1555645165 in words is "one billion, five hundred fifty-five million, six hundred forty-five thousand, one hundred sixty-five".