66119955720 has 256 divisors, whose sum is σ = 258496842240. Its totient is φ = 13129924608.

The previous prime is 66119955691. The next prime is 66119955773. The reversal of 66119955720 is 2755991166.

It is a Harshad number since it is a multiple of its sum of digits (51).

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 63 ways as a sum of consecutive naturals, for example, 7554 + ... + 363726.

It is an arithmetic number, because the mean of its divisors is an integer number (1009753290).

Almost surely, 2^66119955720 is an apocalyptic number.

66119955720 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 66119955720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129248421120).

66119955720 is an abundant number, since it is smaller than the sum of its proper divisors (192376886520).

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

66119955720 is a wasteful number, since it uses less digits than its factorization.

66119955720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356224 (or 356220 counting only the distinct ones).

The product of its (nonzero) digits is 1020600, while the sum is 51.

The spelling of 66119955720 in words is "sixty-six billion, one hundred nineteen million, nine hundred fifty-five thousand, seven hundred twenty".