66998686965120 has 320 divisors, whose sum is σ = 240586344638640. Its totient is φ = 17767605104640.

The previous prime is 66998686965113. The next prime is 66998686965121. The reversal of 66998686965120 is 2156968689966.

66998686965120 is a `hidden beast` number, since 6 + 6 + 9 + 9 + 8 + 6 + 8 + 6 + 96 + 512 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (320).

It is a super-2 number, since 2×66998686965120² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a self number, because there is not a number n which added to its sum of digits gives 66998686965120.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66998686965121) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 5812839 + ... + 12953241.

Almost surely, 2^{66998686965120} is an apocalyptic number.

66998686965120 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 66998686965120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120293172319320).

66998686965120 is an abundant number, since it is smaller than the sum of its proper divisors (173587657673520).

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

66998686965120 is a wasteful number, since it uses less digits than its factorization.

66998686965120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7140615 (or 7140594 counting only the distinct ones).

The product of its (nonzero) digits is 3627970560, while the sum is 81.

The spelling of 66998686965120 in words is "sixty-six trillion, nine hundred ninety-eight billion, six hundred eighty-six million, nine hundred sixty-five thousand, one hundred twenty".