221567904100 has 81 divisors (see below), whose sum is σ = 486580378347. Its totient is φ = 87574654080.

The previous prime is 221567904097. The next prime is 221567904149. The reversal of 221567904100 is 1409765122.

The square root of 221567904100 is 470710.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 15430111524 + 206137792576 = 124218^2 + 454024^2 .

It is a super-2 number, since 2×221567904100² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221567904100.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 484831072 + ... + 484831528.

Almost surely, 2^221567904100 is an apocalyptic number.

221567904100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

221567904100 is the 470710-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221567904100

221567904100 is an abundant number, since it is smaller than the sum of its proper divisors (265012474247).

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

221567904100 is an equidigital number, since it uses as much as digits as its factorization.

221567904100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1134 (or 567 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 37.

The spelling of 221567904100 in words is "two hundred twenty-one billion, five hundred sixty-seven million, nine hundred four thousand, one hundred".