221051345 has 4 divisors (see below), whose sum is σ = 265261620. Its totient is φ = 176841072.

The previous prime is 221051333. The next prime is 221051351. The reversal of 221051345 is 543150122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 106646929 + 114404416 = 10327^2 + 10696^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221051345 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221051345.

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, 22105130 + ... + 22105139.

It is an arithmetic number, because the mean of its divisors is an integer number (66315405).

Almost surely, 2^221051345 is an apocalyptic number.

It is an amenable number.

221051345 is a deficient number, since it is larger than the sum of its proper divisors (44210275).

221051345 is an equidigital number, since it uses as much as digits as its factorization.

221051345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44210274.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 221051345 is about 14867.7955662566. The cubic root of 221051345 is about 604.6411778420.

The spelling of 221051345 in words is "two hundred twenty-one million, fifty-one thousand, three hundred forty-five".