66498969600 has 720 divisors, whose sum is σ = 279541830400. Its totient is φ = 15182069760.

The previous prime is 66498969587. The next prime is 66498969617. The reversal of 66498969600 is 696989466.

It is a tau number, because it is divible by the number of its divisors (720).

It is a super-2 number, since 2×66498969600² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 77413971 + ... + 77414829.

Almost surely, 2^66498969600 is an apocalyptic number.

66498969600 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 66498969600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139770915200).

66498969600 is an abundant number, since it is smaller than the sum of its proper divisors (213042860800).

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

66498969600 is an equidigital number, since it uses as much as digits as its factorization.

66498969600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 913 (or 876 counting only the distinct ones).

The product of its (nonzero) digits is 30233088, while the sum is 63.

The spelling of 66498969600 in words is "sixty-six billion, four hundred ninety-eight million, nine hundred sixty-nine thousand, six hundred".