66998621001312 has 3840 divisors, whose sum is σ = 287039217991680. Its totient is φ = 14772558643200.

The previous prime is 66998621001287. The next prime is 66998621001313. The reversal of 66998621001312 is 21310012689966.

66998621001312 is a `hidden beast` number, since 6 + 6 + 9 + 9 + 8 + 621 + 0 + 0 + 1 + 3 + 1 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66998621001313) by changing a digit.

It is a polite number, since it can be written in 639 ways as a sum of consecutive naturals, for example, 139871859889 + ... + 139871860367.

It is an arithmetic number, because the mean of its divisors is an integer number (74749796352).

Almost surely, 2^{66998621001312} is an apocalyptic number.

66998621001312 is a gapful number since it is divisible by the number (62) 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 66998621001312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143519608995840).

66998621001312 is an abundant number, since it is smaller than the sum of its proper divisors (220040596990368).

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

66998621001312 is a wasteful number, since it uses less digits than its factorization.

66998621001312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 647 (or 630 counting only the distinct ones).

The product of its (nonzero) digits is 1679616, while the sum is 54.

The spelling of 66998621001312 in words is "sixty-six trillion, nine hundred ninety-eight billion, six hundred twenty-one million, one thousand, three hundred twelve".