221656554164660 has 96 divisors (see below), whose sum is σ = 487107653598720. Its totient is φ = 84564990208512.

The previous prime is 221656554164569. The next prime is 221656554164671. The reversal of 221656554164660 is 66461455656122.

It is a self number, because there is not a number n which added to its sum of digits gives 221656554164660.

It is a congruent number.

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, 967425074 + ... + 967654166.

It is an arithmetic number, because the mean of its divisors is an integer number (5074038058320).

Almost surely, 2^{221656554164660} is an apocalyptic number.

221656554164660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221656554164660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243553826799360).

221656554164660 is an abundant number, since it is smaller than the sum of its proper divisors (265451099434060).

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

221656554164660 is a wasteful number, since it uses less digits than its factorization.

221656554164660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235137 (or 235135 counting only the distinct ones).

The product of its (nonzero) digits is 62208000, while the sum is 59.

The spelling of 221656554164660 in words is "two hundred twenty-one trillion, six hundred fifty-six billion, five hundred fifty-four million, one hundred sixty-four thousand, six hundred sixty".