661666500106 has 8 divisors (see below), whose sum is σ = 992572817184. Its totient is φ = 330808894380.

The previous prime is 661666500041. The next prime is 661666500149. The reversal of 661666500106 is 601005666166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×661666500106² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12143860 + ... + 12198223.

It is an arithmetic number, because the mean of its divisors is an integer number (124071602148).

Almost surely, 2^661666500106 is an apocalyptic number.

661666500106 is a deficient number, since it is larger than the sum of its proper divisors (330906317078).

661666500106 is a wasteful number, since it uses less digits than its factorization.

661666500106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24355676.

The product of its (nonzero) digits is 233280, while the sum is 43.

The spelling of 661666500106 in words is "six hundred sixty-one billion, six hundred sixty-six million, five hundred thousand, one hundred six".