66899280650 has 24 divisors (see below), whose sum is σ = 127080169920. Its totient is φ = 26190355760.

The previous prime is 66899280647. The next prime is 66899280683. The reversal of 66899280650 is 5608299866.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 66899280650.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14231540 + ... + 14236239.

It is an arithmetic number, because the mean of its divisors is an integer number (5295007080).

Almost surely, 2^66899280650 is an apocalyptic number.

66899280650 is a deficient number, since it is larger than the sum of its proper divisors (60180889270).

66899280650 is a wasteful number, since it uses less digits than its factorization.

66899280650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28467838 (or 28467833 counting only the distinct ones).

The product of its (nonzero) digits is 11197440, while the sum is 59.

The spelling of 66899280650 in words is "sixty-six billion, eight hundred ninety-nine million, two hundred eighty thousand, six hundred fifty".