221321268 has 48 divisors (see below), whose sum is σ = 655768960. Its totient is φ = 63234432.

The previous prime is 221321267. The next prime is 221321273. The reversal of 221321268 is 862123122.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221321267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 145621 + ... + 147132.

Almost surely, 2^221321268 is an apocalyptic number.

221321268 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

221321268 is an abundant number, since it is smaller than the sum of its proper divisors (434447692).

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

221321268 is a wasteful number, since it uses less digits than its factorization.

221321268 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292773 (or 292765 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 221321268 is about 14876.8702353687. The cubic root of 221321268 is about 604.8871843009.

It can be divided in two parts, 221 and 321268, that added together give a square (321489 = 567²).

The spelling of 221321268 in words is "two hundred twenty-one million, three hundred twenty-one thousand, two hundred sixty-eight".