221565721606000 has 80 divisors (see below), whose sum is σ = 535771080018720. Its totient is φ = 88622125670400.

The previous prime is 221565721605973. The next prime is 221565721606039. The reversal of 221565721606000 is 606127565122.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-3 number, since 3×221565721606000³ (a number of 44 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40162831 + ... + 45345169.

It is an arithmetic number, because the mean of its divisors is an integer number (6697138500234).

Almost surely, 2^{221565721606000} is an apocalyptic number.

221565721606000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221565721606000 is an abundant number, since it is smaller than the sum of its proper divisors (314205358412720).

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

221565721606000 is a wasteful number, since it uses less digits than its factorization.

221565721606000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5203739 (or 5203723 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 43.

The spelling of 221565721606000 in words is "two hundred twenty-one trillion, five hundred sixty-five billion, seven hundred twenty-one million, six hundred six thousand".