221680774658 has 54 divisors (see below), whose sum is σ = 390397302531. Its totient is φ = 94133111688.

The previous prime is 221680774643. The next prime is 221680774699. The reversal of 221680774658 is 856477086122.

It can be written as a sum of positive squares in only one way, i.e., 110840387329 + 110840387329 = 332927^2 + 332927^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=332927.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 927534503 + ... + 927534741.

Almost surely, 2^221680774658 is an apocalyptic number.

221680774658 is a deficient number, since it is larger than the sum of its proper divisors (168716527873).

221680774658 is an frugal number, since it uses more digits than its factorization.

221680774658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 892 (or 447 counting only the distinct ones).

The product of its (nonzero) digits is 9031680, while the sum is 56.

The spelling of 221680774658 in words is "two hundred twenty-one billion, six hundred eighty million, seven hundred seventy-four thousand, six hundred fifty-eight".