221660106665 has 32 divisors (see below), whose sum is σ = 277624972800. Its totient is φ = 169763143680.

The previous prime is 221660106653. The next prime is 221660106737. The reversal of 221660106665 is 566601066122.

It is not a de Polignac number, because 221660106665 - 2⁴ = 221660106649 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2597801 + ... + 2681769.

It is an arithmetic number, because the mean of its divisors is an integer number (8675780400).

Almost surely, 2^221660106665 is an apocalyptic number.

It is an amenable number.

221660106665 is a deficient number, since it is larger than the sum of its proper divisors (55964866135).

221660106665 is a wasteful number, since it uses less digits than its factorization.

221660106665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84257.

The product of its (nonzero) digits is 155520, while the sum is 41.

The spelling of 221660106665 in words is "two hundred twenty-one billion, six hundred sixty million, one hundred six thousand, six hundred sixty-five".