66838575076416 has 1344 divisors, whose sum is σ = 260150059653120. Its totient is φ = 16670032035840.

The previous prime is 66838575076409. The next prime is 66838575076463. The reversal of 66838575076416 is 61467057583866.

It is a happy number.

66838575076416 is a `hidden beast` number, since 6 + 6 + 8 + 3 + 8 + 57 + 507 + 64 + 1 + 6 = 666.

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

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 191 ways as a sum of consecutive naturals, for example, 718284805 + ... + 718377851.

It is an arithmetic number, because the mean of its divisors is an integer number (193564032480).

Almost surely, 2^{66838575076416} is an apocalyptic number.

66838575076416 is a gapful number since it is divisible by the number (66) 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 66838575076416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130075029826560).

66838575076416 is an abundant number, since it is smaller than the sum of its proper divisors (193311484576704).

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

66838575076416 is a wasteful number, since it uses less digits than its factorization.

66838575076416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93134 (or 93112 counting only the distinct ones).

The product of its (nonzero) digits is 1219276800, while the sum is 72.

The spelling of 66838575076416 in words is "sixty-six trillion, eight hundred thirty-eight billion, five hundred seventy-five million, seventy-six thousand, four hundred sixteen".