221256560 has 60 divisors (see below), whose sum is σ = 598419288. Its totient is φ = 75858048.

The previous prime is 221256533. The next prime is 221256571. The reversal of 221256560 is 65652122.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24302 + ... + 32141.

Almost surely, 2^221256560 is an apocalyptic number.

221256560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221256560 is an abundant number, since it is smaller than the sum of its proper divisors (377162728).

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

221256560 is a wasteful number, since it uses less digits than its factorization.

221256560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56470 (or 56457 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 29.

The square root of 221256560 is about 14874.6952909967. The cubic root of 221256560 is about 604.8282279920.

The spelling of 221256560 in words is "two hundred twenty-one million, two hundred fifty-six thousand, five hundred sixty".