666277496640 has 448 divisors, whose sum is σ = 2844281433600. Its totient is φ = 143333425152.

The previous prime is 666277496593. The next prime is 666277496701. The reversal of 666277496640 is 46694772666.

It is a tau number, because it is divible by the number of its divisors (448).

It is a super-3 number, since 3×666277496640³ (a number of 36 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 704146 + ... + 1352174.

Almost surely, 2^666277496640 is an apocalyptic number.

666277496640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666277496640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1422140716800).

666277496640 is an abundant number, since it is smaller than the sum of its proper divisors (2178003936960).

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

666277496640 is a wasteful number, since it uses less digits than its factorization.

666277496640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 648079 (or 648063 counting only the distinct ones).

The product of its (nonzero) digits is 109734912, while the sum is 63.

The spelling of 666277496640 in words is "six hundred sixty-six billion, two hundred seventy-seven million, four hundred ninety-six thousand, six hundred forty".