221655321651654 has 96 divisors (see below), whose sum is σ = 547813961270784. Its totient is φ = 64115992765440.

The previous prime is 221655321651641. The next prime is 221655321651697. The reversal of 221655321651654 is 456156123556122.

221655321651654 is a `hidden beast` number, since 2 + 2 + 1 + 6 + 5 + 53 + 21 + 6 + 516 + 54 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 221655321651654.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 47754139 + ... + 52189734.

It is an arithmetic number, because the mean of its divisors is an integer number (5706395429904).

Almost surely, 2^{221655321651654} is an apocalyptic number.

221655321651654 is an abundant number, since it is smaller than the sum of its proper divisors (326158639619130).

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

221655321651654 is a wasteful number, since it uses less digits than its factorization.

221655321651654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99944402 (or 99944399 counting only the distinct ones).

The product of its digits is 12960000, while the sum is 54.

The spelling of 221655321651654 in words is "two hundred twenty-one trillion, six hundred fifty-five billion, three hundred twenty-one million, six hundred fifty-one thousand, six hundred fifty-four".