213911662666 has 32 divisors (see below), whose sum is σ = 354169943568. Its totient is φ = 96268124160.

The previous prime is 213911662663. The next prime is 213911662667. The reversal of 213911662666 is 666266119312.

It can be written as a sum of positive squares in 8 ways, for example, as 7872835441 + 206038827225 = 88729^2 + 453915^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (213911662663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1943050 + ... + 2050186.

Almost surely, 2^213911662666 is an apocalyptic number.

213911662666 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

213911662666 is a deficient number, since it is larger than the sum of its proper divisors (140258280902).

213911662666 is a wasteful number, since it uses less digits than its factorization.

213911662666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109066.

The product of its digits is 839808, while the sum is 49.

The spelling of 213911662666 in words is "two hundred thirteen billion, nine hundred eleven million, six hundred sixty-two thousand, six hundred sixty-six".