66815910000 has 900 divisors, whose sum is σ = 276281405400. Its totient is φ = 15023232000.

The previous prime is 66815909989. The next prime is 66815910011. The reversal of 66815910000 is 1951866.

66815910000 is a `hidden beast` number, since 6 + 68 + 1 + 591 + 0 + 0 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (66815909989) and next prime (66815910011).

It is a tau number, because it is divible by the number of its divisors (900).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 179 ways as a sum of consecutive naturals, for example, 480689931 + ... + 480690069.

Almost surely, 2^66815910000 is an apocalyptic number.

66815910000 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 66815910000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138140702700).

66815910000 is an abundant number, since it is smaller than the sum of its proper divisors (209465495400).

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

66815910000 is a wasteful number, since it uses less digits than its factorization.

66815910000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296 (or 265 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The spelling of 66815910000 in words is "sixty-six billion, eight hundred fifteen million, nine hundred ten thousand".