221057555 has 8 divisors (see below), whose sum is σ = 265352112. Its totient is φ = 176790688.

The previous prime is 221057537. The next prime is 221057561. The reversal of 221057555 is 555750122.

221057555 = 2700² + 2701² + ... + 2729².

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221057555 - 2⁸ = 221057299 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20597 + ... + 29433.

It is an arithmetic number, because the mean of its divisors is an integer number (33169014).

Almost surely, 2^221057555 is an apocalyptic number.

221057555 is a deficient number, since it is larger than the sum of its proper divisors (44294557).

221057555 is an equidigital number, since it uses as much as digits as its factorization.

221057555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13845.

The product of its (nonzero) digits is 17500, while the sum is 32.

The square root of 221057555 is about 14868.0044054338. The cubic root of 221057555 is about 604.6468398547.

The spelling of 221057555 in words is "two hundred twenty-one million, fifty-seven thousand, five hundred fifty-five".