2166515018 has 4 divisors (see below), whose sum is σ = 3249772530. Its totient is φ = 1083257508.

The previous prime is 2166515017. The next prime is 2166515023. The reversal of 2166515018 is 8105156612.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 2165692369 + 822649 = 46537^2 + 907^2 .

It is not an unprimeable number, because it can be changed into a prime (2166515017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 541628753 + ... + 541628756.

Almost surely, 2^2166515018 is an apocalyptic number.

2166515018 is a deficient number, since it is larger than the sum of its proper divisors (1083257512).

2166515018 is a wasteful number, since it uses less digits than its factorization.

2166515018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1083257511.

The product of its (nonzero) digits is 14400, while the sum is 35.

The square root of 2166515018 is about 46545.8378160712. The cubic root of 2166515018 is about 1293.9591559036.

The spelling of 2166515018 in words is "two billion, one hundred sixty-six million, five hundred fifteen thousand, eighteen".