221246540 has 12 divisors (see below), whose sum is σ = 464617776. Its totient is φ = 88498608.

The previous prime is 221246533. The next prime is 221246549. The reversal of 221246540 is 45642122.

It is not an unprimeable number, because it can be changed into a prime (221246549) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5531144 + ... + 5531183.

It is an arithmetic number, because the mean of its divisors is an integer number (38718148).

Almost surely, 2^221246540 is an apocalyptic number.

221246540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221246540 is an abundant number, since it is smaller than the sum of its proper divisors (243371236).

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

221246540 is a wasteful number, since it uses less digits than its factorization.

221246540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11062336 (or 11062334 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 221246540 is about 14874.3584735611. The cubic root of 221246540 is about 604.8190976107.

Adding to 221246540 its reverse (45642122), we get a palindrome (266888662).

The spelling of 221246540 in words is "two hundred twenty-one million, two hundred forty-six thousand, five hundred forty".