66735872658720 has 384 divisors, whose sum is σ = 247366770497280. Its totient is φ = 16745909207040.

The previous prime is 66735872658713. The next prime is 66735872658727. The reversal of 66735872658720 is 2785627853766.

66735872658720 is a `hidden beast` number, since 6 + 6 + 7 + 35 + 8 + 7 + 2 + 6 + 587 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (66735872658713) and next prime (66735872658727).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (66735872658727) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 362187415 + ... + 362371625.

It is an arithmetic number, because the mean of its divisors is an integer number (644184298170).

Almost surely, 2^{66735872658720} is an apocalyptic number.

66735872658720 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 66735872658720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123683385248640).

66735872658720 is an abundant number, since it is smaller than the sum of its proper divisors (180630897838560).

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

66735872658720 is a wasteful number, since it uses less digits than its factorization.

66735872658720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189185 (or 189171 counting only the distinct ones).

The product of its (nonzero) digits is 1422489600, while the sum is 72.

The spelling of 66735872658720 in words is "sixty-six trillion, seven hundred thirty-five billion, eight hundred seventy-two million, six hundred fifty-eight thousand, seven hundred twenty".