66606797318400 has 216 divisors, whose sum is σ = 244240342374560. Its totient is φ = 17761812572160.

The previous prime is 66606797318239. The next prime is 66606797318401. The reversal of 66606797318400 is 481379760666.

It is a tau number, because it is divible by the number of its divisors (216).

It is not an unprimeable number, because it can be changed into a prime (66606797318401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 192555202 + ... + 192900801.

Almost surely, 2^{66606797318400} is an apocalyptic number.

66606797318400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66606797318400 is an abundant number, since it is smaller than the sum of its proper divisors (177633545056160).

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

66606797318400 is a wasteful number, since it uses less digits than its factorization.

66606797318400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385456038 (or 385456013 counting only the distinct ones).

The product of its (nonzero) digits is 54867456, while the sum is 63.

The spelling of 66606797318400 in words is "sixty-six trillion, six hundred six billion, seven hundred ninety-seven million, three hundred eighteen thousand, four hundred".