1745394221 has 4 divisors (see below), whose sum is σ = 1747856700. Its totient is φ = 1742931744.

The previous prime is 1745394197. The next prime is 1745394239. The reversal of 1745394221 is 1224935471.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1224935471 = 251 ⋅4880221.

It can be written as a sum of positive squares in 2 ways, for example, as 1072562500 + 672831721 = 32750^2 + 25939^2 .

It is a cyclic number.

It is not a de Polignac number, because 1745394221 - 2¹⁰ = 1745393197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1745394121) 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, 1230176 + ... + 1231593.

It is an arithmetic number, because the mean of its divisors is an integer number (436964175).

Almost surely, 2^1745394221 is an apocalyptic number.

It is an amenable number.

1745394221 is a deficient number, since it is larger than the sum of its proper divisors (2462479).

1745394221 is an equidigital number, since it uses as much as digits as its factorization.

1745394221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2462478.

The product of its digits is 60480, while the sum is 38.

The square root of 1745394221 is about 41777.9154697790. The cubic root of 1745394221 is about 1204.0130049128.

The spelling of 1745394221 in words is "one billion, seven hundred forty-five million, three hundred ninety-four thousand, two hundred twenty-one".