221657221077736 has 8 divisors (see below), whose sum is σ = 415607289520770. Its totient is φ = 110828610538864.

The previous prime is 221657221077727. The next prime is 221657221077751. The reversal of 221657221077736 is 637770122756122.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 170746227660100 + 50910993417636 = 13066990^2 + 7135194^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13853576317351 + ... + 13853576317366.

Almost surely, 2^{221657221077736} is an apocalyptic number.

It is an amenable number.

221657221077736 is a deficient number, since it is larger than the sum of its proper divisors (193950068443034).

221657221077736 is a wasteful number, since it uses less digits than its factorization.

221657221077736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27707152634723 (or 27707152634719 counting only the distinct ones).

The product of its (nonzero) digits is 20744640, while the sum is 58.

The spelling of 221657221077736 in words is "two hundred twenty-one trillion, six hundred fifty-seven billion, two hundred twenty-one million, seventy-seven thousand, seven hundred thirty-six".