66101948640 has 1728 divisors, whose sum is σ = 312266695104. Its totient is φ = 13042778112.

The previous prime is 66101948629. The next prime is 66101948663. The reversal of 66101948640 is 4684910166.

66101948640 is a `hidden beast` number, since 66 + 101 + 9 + 486 + 4 + 0 = 666.

It is a super-2 number, since 2×66101948640² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 421031442 + ... + 421031598.

It is an arithmetic number, because the mean of its divisors is an integer number (180709893).

Almost surely, 2^66101948640 is an apocalyptic number.

66101948640 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 66101948640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156133347552).

66101948640 is an abundant number, since it is smaller than the sum of its proper divisors (246164746464).

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

66101948640 is a wasteful number, since it uses less digits than its factorization.

66101948640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231 (or 204 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The spelling of 66101948640 in words is "sixty-six billion, one hundred one million, nine hundred forty-eight thousand, six hundred forty".