66904903680 has 416 divisors, whose sum is σ = 231575952000. Its totient is φ = 16434855936.

The previous prime is 66904903649. The next prime is 66904903693. The reversal of 66904903680 is 8630940966.

It is a super-2 number, since 2×66904903680² (a number of 22 digits) contains 22 as substring.

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 31 ways as a sum of consecutive naturals, for example, 43191546 + ... + 43193094.

Almost surely, 2^66904903680 is an apocalyptic number.

66904903680 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 66904903680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115787976000).

66904903680 is an abundant number, since it is smaller than the sum of its proper divisors (164671048320).

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

66904903680 is a wasteful number, since it uses less digits than its factorization.

66904903680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1637 (or 1615 counting only the distinct ones).

The product of its (nonzero) digits is 1679616, while the sum is 51.

The spelling of 66904903680 in words is "sixty-six billion, nine hundred four million, nine hundred three thousand, six hundred eighty".