66826166400 has 576 divisors, whose sum is σ = 282631702080. Its totient is φ = 15273308160.

The previous prime is 66826166387. The next prime is 66826166411. The reversal of 66826166400 is 466162866.

66826166400 is a `hidden beast` number, since 6 + 6 + 82 + 6 + 166 + 400 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a super-3 number, since 3×66826166400³ (a number of 33 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 5437062 + ... + 5449338.

Almost surely, 2^66826166400 is an apocalyptic number.

66826166400 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 66826166400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141315851040).

66826166400 is an abundant number, since it is smaller than the sum of its proper divisors (215805535680).

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

66826166400 is a wasteful number, since it uses less digits than its factorization.

66826166400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12323 (or 12294 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 45.

The spelling of 66826166400 in words is "sixty-six billion, eight hundred twenty-six million, one hundred sixty-six thousand, four hundred".