221740356 has 12 divisors (see below), whose sum is σ = 517394192. Its totient is φ = 73913448.

The previous prime is 221740339. The next prime is 221740361. The reversal of 221740356 is 653047122.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9239170 + ... + 9239193.

Almost surely, 2^221740356 is an apocalyptic number.

It is an amenable number.

221740356 is an abundant number, since it is smaller than the sum of its proper divisors (295653836).

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

221740356 is a wasteful number, since it uses less digits than its factorization.

221740356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18478370 (or 18478368 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 30.

The square root of 221740356 is about 14890.9487944859. The cubic root of 221740356 is about 605.2687429331.

Adding to 221740356 its reverse (653047122), we get a palindrome (874787478).

The spelling of 221740356 in words is "two hundred twenty-one million, seven hundred forty thousand, three hundred fifty-six".