66799691010 has 64 divisors (see below), whose sum is σ = 191835020160. Its totient is φ = 16443000000.

The previous prime is 66799690831. The next prime is 66799691017. The reversal of 66799691010 is 1019699766.

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

It is not an unprimeable number, because it can be changed into a prime (66799691017) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9512116 + ... + 9519135.

It is an arithmetic number, because the mean of its divisors is an integer number (2997422190).

Almost surely, 2^66799691010 is an apocalyptic number.

66799691010 is an abundant number, since it is smaller than the sum of its proper divisors (125035329150).

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

66799691010 is a wasteful number, since it uses less digits than its factorization.

66799691010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19031280 (or 19031274 counting only the distinct ones).

The product of its (nonzero) digits is 1102248, while the sum is 54.

The spelling of 66799691010 in words is "sixty-six billion, seven hundred ninety-nine million, six hundred ninety-one thousand, ten".