221361902666 has 8 divisors (see below), whose sum is σ = 332049080484. Its totient is φ = 110678875840.

The previous prime is 221361902659. The next prime is 221361902693. The reversal of 221361902666 is 666209163122.

It can be written as a sum of positive squares in 2 ways, for example, as 151726609441 + 69635293225 = 389521^2 + 263885^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 900815 + ... + 1119906.

Almost surely, 2^221361902666 is an apocalyptic number.

221361902666 is a deficient number, since it is larger than the sum of its proper divisors (110687177818).

221361902666 is a wasteful number, since it uses less digits than its factorization.

221361902666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2075496.

The product of its (nonzero) digits is 279936, while the sum is 44.

The spelling of 221361902666 in words is "two hundred twenty-one billion, three hundred sixty-one million, nine hundred two thousand, six hundred sixty-six".