666459281520 has 120 divisors (see below), whose sum is σ = 2238496829712. Its totient is φ = 177698304000.

The previous prime is 666459281519. The next prime is 666459281549. The reversal of 666459281520 is 25182954666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×666459281520² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5586495 + ... + 5704545.

Almost surely, 2^666459281520 is an apocalyptic number.

666459281520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

666459281520 is an abundant number, since it is smaller than the sum of its proper divisors (1572037548192).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

666459281520 is a wasteful number, since it uses less digits than its factorization.

666459281520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125911 (or 125902 counting only the distinct ones).

The product of its (nonzero) digits is 6220800, while the sum is 54.

The spelling of 666459281520 in words is "six hundred sixty-six billion, four hundred fifty-nine million, two hundred eighty-one thousand, five hundred twenty".