213506246643666 has 16 divisors (see below), whose sum is σ = 427012834809888. Its totient is φ = 71168691960800.

The previous prime is 213506246643617. The next prime is 213506246643671. The reversal of 213506246643666 is 666346642605312.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5710680 + ... + 21438851.

It is an arithmetic number, because the mean of its divisors is an integer number (26688302175618).

Almost surely, 2^{213506246643666} is an apocalyptic number.

213506246643666 is an abundant number, since it is smaller than the sum of its proper divisors (213506588166222).

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

213506246643666 is a wasteful number, since it uses less digits than its factorization.

213506246643666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28460217.

The product of its (nonzero) digits is 134369280, while the sum is 60.

The spelling of 213506246643666 in words is "two hundred thirteen trillion, five hundred six billion, two hundred forty-six million, six hundred forty-three thousand, six hundred sixty-six".