665521070115 has 32 divisors (see below), whose sum is σ = 1162074412800. Its totient is φ = 322555317120.

The previous prime is 665521070111. The next prime is 665521070147. The reversal of 665521070115 is 511070125566.

It is a happy number.

It is not a de Polignac number, because 665521070115 - 2² = 665521070111 is a prime.

It is a super-2 number, since 2×665521070115² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (665521070111) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 319720 + ... + 1197189.

It is an arithmetic number, because the mean of its divisors is an integer number (36314825400).

Almost surely, 2^665521070115 is an apocalyptic number.

665521070115 is a deficient number, since it is larger than the sum of its proper divisors (496553342685).

665521070115 is a wasteful number, since it uses less digits than its factorization.

665521070115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1519587.

The product of its (nonzero) digits is 63000, while the sum is 39.

The spelling of 665521070115 in words is "six hundred sixty-five billion, five hundred twenty-one million, seventy thousand, one hundred fifteen".