664862540181 has 48 divisors (see below), whose sum is σ = 1068728495040. Its totient is φ = 366148823040.

The previous prime is 664862540143. The next prime is 664862540183. The reversal of 664862540181 is 181045268466.

It is not a de Polignac number, because 664862540181 - 2⁷ = 664862540053 is a prime.

It is a super-2 number, since 2×664862540181² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664862540183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2189301 + ... + 2474421.

It is an arithmetic number, because the mean of its divisors is an integer number (22265176980).

Almost surely, 2^664862540181 is an apocalyptic number.

It is an amenable number.

664862540181 is a deficient number, since it is larger than the sum of its proper divisors (403865954859).

664862540181 is a wasteful number, since it uses less digits than its factorization.

664862540181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285714 (or 285707 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 51.

The spelling of 664862540181 in words is "six hundred sixty-four billion, eight hundred sixty-two million, five hundred forty thousand, one hundred eighty-one".