66501615666610 has 64 divisors (see below), whose sum is σ = 120628110556800. Its totient is φ = 26395791127552.

The previous prime is 66501615666527. The next prime is 66501615666611. The reversal of 66501615666610 is 1666651610566.

It is not an unprimeable number, because it can be changed into a prime (66501615666611) 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, 4451536521 + ... + 4451551459.

It is an arithmetic number, because the mean of its divisors is an integer number (1884814227450).

Almost surely, 2^{66501615666610} is an apocalyptic number.

66501615666610 is a deficient number, since it is larger than the sum of its proper divisors (54126494890190).

66501615666610 is a wasteful number, since it uses less digits than its factorization.

66501615666610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20955.

The product of its (nonzero) digits is 6998400, while the sum is 55.

The spelling of 66501615666610 in words is "sixty-six trillion, five hundred one billion, six hundred fifteen million, six hundred sixty-six thousand, six hundred ten".