398105911666 has 8 divisors (see below), whose sum is σ = 598448628864. Its totient is φ = 198623035380.

The previous prime is 398105911649. The next prime is 398105911739. The reversal of 398105911666 is 666119501893.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 214959070 + ... + 214960921.

It is an arithmetic number, because the mean of its divisors is an integer number (74806078608).

Almost surely, 2^398105911666 is an apocalyptic number.

398105911666 is a deficient number, since it is larger than the sum of its proper divisors (200342717198).

398105911666 is a wasteful number, since it uses less digits than its factorization.

398105911666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429920456.

The product of its (nonzero) digits is 2099520, while the sum is 55.

It can be divided in two parts, 398105 and 911666, that added together give a triangular number (1309771 = T₁₆₁₈).

The spelling of 398105911666 in words is "three hundred ninety-eight billion, one hundred five million, nine hundred eleven thousand, six hundred sixty-six".